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WORLD'S  LARGEST 


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NOW  AT  YOUR  DEALERS! 

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Receiver:  Sensitivity:  SIN  AD  -5uv  for  12db,  luv  provides  20  db  quieting. 

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PETERBOROUGH,    NEW    HAMPSHIRE    03458 


73  Magazine /1 09,  October  1969 


Features 

2  de  W2NSD/1 

II  Sotderiog  Aid 
13  Try  This  One 
31  Autobandwidth 

39  ^Mobile  Heater  Switching 

49  IShJetded  Braid 

75  Simpte  Code  Oscillator 

III  New  PrcxJucts 

113  ^opagati  on 

114  Crossword  Puzzle 
122  euy  or  Rent 

128  ZL  to  SM  Moonbounce 

128  New  Amateur  TV  Record  in  VK ! 

128  New  1296  mhz  VK  Record 

131  Errata 

134  L«ttsr^ 

141  Caveat  Emptor 

144  Index  to  Advertisers 


STAFF 

Editors 

Wayne  Green  W2NSD/1 
Kayla  Blook  WIEMV 

Advertising 
Diane  Shaw 

Production 
Roger  Block 
Phil  Price 
Nellie  Sildar 
Jeff  Barsanti 
Jane  Tracey 
Whitney  Tobias 

Art 

Bill  Moreflo 
Mike  Baltin 

Circulation 

Lin  Green 
Dorothy  Gibson 
Carol  Ring 

Comptroller 
Joe  LaVigne 

Propagation 

John  Nelson 

WrW  Editor 

Dave  Mann  K2AGZ 

BoQks 

Wafter  Manek 
Mark  Kearney 


8 
12 
20 
24 
28 
32 
34 
40 
42 
46 
50 
52 
54 
58 
62 
64 
66 
S8 
70 
73 
76 
83 
86 
108 
116 
123 
124 
132 


Contents 

A  Super^Gain  Antenna  for  40  Meters    .,..,,,,,». W4ISIVK 

Nine  db  on  40  meters  might  be  called  *'super/* 

DX  Corner    , ___.,, K2AG2 

WTW  reports  and  other  DX  jazz. 

FET  Chirper , .,.....,   K6QKL 

Signet  source  for  peaking  converters  for  optimum  signal /noise* 

The  inside  Info  on  Alexander  Graham    .,**.,,,.,.,,.,,  ,W2FEZ 
Or— how  the  telephone  really  works. 

Leaky  Lines    ,,-,,,,.,... ,  .  ^  ,  .  •  . K2AGZ 

Similar  to  "Grumbles/'  but  by  a  licensed  amateur,  not  a  CB'er 

Scope  Calibrator  , .  .  . . , ,  ,  , , _ W10LP 

Gadget  you  can  build  to  improve  your  scope. 

Vidiots  That  Have  Known  Me  .  > * ,  *K1  YSD 

Sense  of  iiumor  test.  If  you  flunk,  go  back  to  11  meters. 

The  Protector , ..,.,.  WA0  HKC 

Protects  your  gear  from  sudden  line  voltage  surges  and  interruptions. 

Slower  Tuning  Rates  for  Older  Receivers    . , , ,  W4RNL 

Just  like  band  spread. 

Positive  Identification  of  Calibrator  Harnrionte    .__->,,-.,  K5LLI 

Keeps  you  off  6950  and  other  poor  DX  bands. 

Adapting  AM  Transmitters  to  FM ,,,.,.,.  .WA4UZM 

Good  Heavens,  is  everyone  going  on  VHF  FM? 

CB  Sets  on  Six    ,  .  . WB2FHW 

No  need  to  junk  that  C8  rig  when  you  get  your  Tech  ticket. 

Proportional  Controt  Crystal  Oven   ..,*,*,,*,,,,** W2CLL 

You  need  this  sort  of  thing  for  moonbouni:^  work  and  such. 

A  Crystal  Filter  Phasing  Control  .  . ,,,,.. .  ,  .  ,  ,W2LT 

Look  at  the  i-f  response  in  Fig.  10  and  be  amazed. 

Grounded  Grid  Filament  Chokes    . , , W2|K 

You  need  these  for  linear  amplifiers. 

Equipment  Cabinets  with  Style  .  *  .  .  * •  ,  .  .  .  .W20LP 

Make  it  look  commercial. 

VHF-FM:  Part  I    , ,  .^. ...•-.. . . .  .  _  WB2AEB 

Advantages  and  practices.  When  sre  you  going  on  FM? 

Bring  Back  the  Q  Multiplier , W8RHR 

Invaluable  for  CW,  notches  out  AM  carriers,  etc. 

Activation  in  VP2 ,  .  . VP2AC 

Anguilla  Island  activated. 

The  CR  Beam    .  .  .  ,  , _  .  _  _ WA4FDQ 

Two  meter  corner  reflector  beam. 

The  ARRL  Board  and  Amateur  Radio    ,  ^  ,**.**.<**,,  , 
An  ex -ARRL  Director  evaluates  the  latest  board  meeting, 

A  Cheap  and  Easy  Power  Supply 

For  a  sideband  transceiver. 

Extra  Class  License  Course,  Part  fX 

Modulation.  We'll  have  lots  of  arguments  on  this  one. 

Ham  Jamboree •  , 

Scouts  hit  the  ham  bands  every  October- 
Operation  Cat's  Paw .•.*..•,..... 

Whimsy. 

Knight  V-107  VFO  for  Six  and  Two  Meters , K6GKX 

Test  report  by  a  happy  user. 

Careers  in  the  F AA  .  . ,,.,.. , W6JTT 

Get  on  the  government  payrolL 

Youth  Forum   ..,....»,•• •....,....* WAIGEK 

Teenagers,  arisel 


,  _W7ZC 


K4FQU 


.  .Staff 


WB6IZF 


..W7ZC 


i 


73  Magazine  is  published  by  73  Inc.^  Peterborough,  N,H.  03458,  Subscription  rate:  $12.00  for  three 
yearSj  $6.00  for  one  year.  Second  Class  Postage  paid  at  Peterborough,  New  Hampshire,  and  at 
additional  mailinfi  offices.  Printed  at  Pontiac,  Illinois,  U.S.A.  Entire  contents  copyright  1969  by  73 
Inc,  Peterborougn,  New  Hampshire  03458.  Address  label  cypher:  your  call  letters  should  follow  your 
name.  If  we've  had  to  make  up  a  call  just  drop  us  a  note  and  we'll  change  it  to  your  real  call.  The 
number  under  the  caU  is  our  code  for  the  last  issue  on  your  subscription.  The  first  number  is  the 
month,  the  second  the  year  of  the  last  issue,  50  would  indicate  expiration  with  May,  1970.  Renewal 
notices  are  prepared  ahead  of  time  and  you  may  receive  one  or  two  after  your  subscription  has  been 
renewed.  View  tlus  situation  with  humor  and  tolerance.  Tell  your  friends  about  it,  ii  you  must^  but 
don^t  feel  it  necessary  to  teU  us.  We  already  know  all  too  well  about  it. 


OCTOBER  1969 


1 


Gravity  Waves 
Solution  to  Vietnam? 
Making  Extra  Money 
Making  $1,000,0001 
Reactionaries 
Marathon  Nets 
FCC  Actions 


...de  W2NSD/1 


Wayne  Green 


p 


Gravity  Waves 

My  thanks  to  old  friend  Neil  W20LU  for 
sending  in  a  clipping  from  the  New  York 
Times  announcing  that  Professor  Weber  of 
the  University  of  Maryland  has  detected 
gravitation  waves.  The  existence  of  gravita- 
tional radiation  is  predicted  by  Einstein^s 
General  Theory  of  Relativity  and  Professor 
Weber  beheves  that  he  has  experimentally 
verified  Einstein's  prediction* 

A  century  ago  Maxwell  predicted  from 
mathematical  calculations  that  there  were 
other  types  of  electro-magnetic  radiation 
than  light  rays.  In  1888  Hertz  confirmed 
Maxwell's  predictions  and  opened  the  radio 
spectrum. 

As  I  mentioned  a  few  months  ago^  here  is 
a  field  that  is  wide  open  for  the  amateur. 
There  are  no  professionals  in  the  field  yet. 
What,  all  of  us  want  to  know,  is  the  velocity 
of  propagation  of  a  gravity  wave?  Speed  of 
light?  Instantaneous?  If  it  is  faster  then  it 
would  make  a  wonderful  communication 
medium  for  interstellar  contacts  .  .  ,  and 
miglit  explain  how  those  pesky  UFO's  are 
able  to  get  here  from  planetary  systems  so 

far  away  that  reputable  scientists  say  that 
they  cannot  exist  just  because  there  is  no 
possible  way  for  them  to  come  that  distance. 
If  you  have  any  info  to  pass  along  on 
gravity  generators  or  detectors,  let's  pass  it 
along  through  73. 

Vietnam  Solution? 

The  educated  opinion  seems  to  be  that 
President  Nixon  has  been  hoping  that  he 
could  use  the  same  route  for  settling  the  war 
that  Eisenhower  used  for  closing  out  the 
Korean  conflict.  That  meant  working 
through  Moscow,  who,  because  of  the  Chi- 
nese difficulties,  were  supposed  to  be 
anxious  to  accomodate  the  U,S, 

This  approach  doesn't  seem  to  have 
worked   out   in  practice  at  all,  a  situation 


which  leaves  us  still  boiling  in  our  own  kettle 
of  soup.  Unilateral  disengagement  means, 
essentially,  the  slaughter  of  most  of  South 
Vietnam,  the  historic  consequence  of  losing 
a  war  in  Asia.  This,  in  turn,  can  hardly  help 
the  non-communist  forces  in  Laos,  Thailand, 
Cambodia,  Malaysia,  Burma  and  India,  Any 
promises  we  have  made  in  the  past  of  help 
wiU  hardly  be  honored  after  the  disaster  in 
Vietnam,  and  they  know  this* 

Obviously,  getting  out  of  Vietnam  unilat- 
erally is  a  very  bad  solution  to  our  problems. 
Should  we  then  turn  around  and  escalate 
again?  We  have  seen  that  the  communists  are 
able  to  match  every  escalation.  They  have  no 

intention  whatever  of  losing  the  war.  They 
have  been  at  it  for  many  years  there  and  are 
not  about  to  drop  it  now. 

This  is  a  subject  that  can  better  be  argued 
in  a  bo  ok -length  form  than  a  brief  editorial 
comment  such  as  this,  however  I  would  Uke 
to  make  an  abbreviated  suggestion  for  a  new 
course  of  action  that  might  possibly  prove 
more  rewarding.  1  wrote  about  this  a  couple 
years  ago  upon  my  return  from  Asia,  but  not 
much  came  of  it.  The  ideas  still  seem  quite 
valid  .  .  .  perhaps  even  more  valid  than  ever^ 
since  more  options  have  been  tried  in  the 
meanwhile  without  noticeable  success. 

Basically,  I  propose  that  the  Pentagon 
and  the  State  Departments  do  not  have  a 
corner  on  the  U,S,  brain  market.  Experience 
has  rather  indicated  negatively  in  this  re- 
spect. Possibly  then,  we  could  do  better  thaa 
depend  upon  them  for  our  total  effort  in 
Vietnam,  directing  the  fighting  and  peace 
talks,  which  about  sums  up  our  activities 
there. 

Just  suppose  that  we  decided  to  fight  a 
much  more  basic  fight,  using  our  biggest 
weapon?  The  bomb?  No,  not  at  all.  The 
battle  between  communism  and  capitalism  is 


73  MAGAZINE 


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INTERNATIONAL 


CRYSTAL  MFG.  CO.,  INC. 

10  NO.  LEE    •    OKUA.  CITY,  OKLA.  73102 


OCTOBER    1969 


wmm 


most  fundamental.  Why  not  use  capitalism 
as  a  weapon?  This  is  one  weapon  that  has 
been  almost  irrestible  so  far  and  yet  we  have 
made  little  effort  to  use  it. 

For  a  fraction  of  the  $100  million  a  day 
we  are  spending  in  Vietnam  we  could  ship 
production  machinery  from  the  U.S,  to  set 
up  factories  around  Vietnam.  I  envision  a 
change  from  the  present  agricultural  system 
to  a  half  agricultural,  half  industrial  system, 
with  factories  spread  out  so  that  workers  can 
continue  to  farm  part  time,  I  wonder  if  this 
isn*t  a  happier  way  of  living  than  our 
all-or-nothing  arrangement? 

Factories  in  undeveloped  countries  are 
rather  basic  affairs  and  far  less  expensive 
than  those  in  our  country.  With  a  relatively 
smaH  investment  we  could  spread  factories 
all  over  Vietnam,  providing  jobs  part  time  in 
hundreds  of  villages.  Would  the  people  make 
the  change?  If  the  incentive  is  there,  they 
win.  The  incentive  that  I  have  seen  change 
one  country  after  another  into  industrial 
countries  has  been  the  availability  of  inex- 
pensive cars  and  television  sets.  People  wiU 
work  incredibly  hard  for  these  pleasures. 

Suppose  we  set  up  a  few  dozen  factories 
making  prefab  huts  and  basic  furniture  and 
gave  these  products  to  the  Vietnamese,  along 
with  a  small  plot  of  land  for  a  garden?  Not 
only  would  we  be  able  to  clean  up  the 
miserable  camps  now  housing  thousands  of 
refugees,  but  we  would  also  have  something 
very  interesting  to  offer  defectors  from  the 
North.  Cars,  TV,  and  other  luxuries  would 
have  to  be  earned. 

The  whole  bill  for  a  give-away  program 
like  that  might  come  to  $1000  per  defector, 
but  that  is  a  small  fraction  of  what  we  are 
paying  right  now  to  try  and  kill  them  as  they 
come  down  to  fight.  It  is  costing  us  some 
500  times  that  much! 

Once  we  convert  Vietnam  to  a  capitalistic 
system,  they  will  be  forever  broken  away 
from  the  old  patterns  and  can  soon  take 
their  place  among  those  Asian  countries  who 
have  made  the  change  *  .  *  Singapore  ,  ,  , 
Thailand  ,  -  ,  Japan,  There  are  plenty  of 
markets  in  Asia  for  products  manufactured 
in  Vietnam  since  few  of  the  neighboring 
countries  are  developed. 

Does  that  sound  better  than  the  alterna- 


tives of  fight  harder  or  quit? 

Danger 

As  those  of  you  who  know  me  personally 
know,  I  love  to  eat  and  as  a  result  I  am 
generally  a  bit  on  the  heavy  side.  Every 
couple  of  years  or  so  I  go  on  a  diet  and  take 
off  the  accumulated  layer.  This  summer^ 
egged  on  by  the  wonders  of  the  Doctor's 
Diet,  a  lovely  invention  wherein  you  eat 
meat  and  drink  water,  .  ,and  not  much  else,  1 
decided  to  make  the  plunge.  The  book  said 
that  1  could  also  drink  all  of  the  diet  soda  1 
wanted  along  with  the  diet,  so  I  loaded  up 
on  my  favorite  flavors  of  "tonic,"  as  they 
call  it  up  here  in  New  Hampshire,  all  sugar 
free. 

Fat  free  beef  and  fat  free  chicken  left  me 
with  plenty  of  hunger  pangs,  but  the  diet 
soda  filled  up  the  empty  spaces  and  I  found 
that  I  was  drinking  more  and  more  each  day, 
getting  up  to  some  four  bottles  a  day.  No 
harm  done,  so  why  not? 

Along  about  the  third  day  I  began  to  find 
it  difficult  to  focus  my  eyes  and  I  started 
having  periods  of  vertigo.  This  got  progress- 
ively  worse  and  by  the  seventh  day  I 
couldn't  even  see  to  type,  much  less  read 
manuscripts  and  proof-read  articles •  My  eyes 
just  couldn't  focus  any  more  at  all,  I  realized 
that  meat  certainly  wouldn't  do  this  to  me, 
and  since  the  only  other  thing  1  was  eating 
was  diet  soda,  it  obviously  had  to  be  that.  I 
stopped. 

Within  a  couple  of  days  the  headaches 
stopped,  the  vertigo  stopped  and  my  eye- 
sight began  to  improve.  After  a  week  I  could 
read  medium-sized  print  again  and  type. 

The  secret  was  right  there  on  each  bottle, 
if  I  had  taken  the  time  to  read  the  fine  print 
while  my  eyes  were  still  working.  That  stuff 
is  supposed  to  be  only  for  people  who  have 
been  requested  by  a  doctor  to  restrict  their 
intake  of  sugar  .  .  ,  diabetics.  In  moderation 
I  suppose  it  would  not  cause  noticeable 
difficulty.  Who  would  notice  his  eyes  slowly 
deteriorating  over  a  period  of  weeks  or 
months  and  tie  it  in  with  diet  soda?  Even 
occasional  headaches  and  vertigo  might  not 
be  suspected.  And  who  knows  what  other 
damage  these  beverages  oiay  be  doing?  They 
certainly  must  be  able  to  have  a  profound 
effect  on  the  human  body  to  be  able  to  do 
me  in  so  quickly  on  such  a  small  dose. 


73  MAGAZINE 


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•  Test  and  Lab  Instruments  ,  .  ,  A 
complete  line  of  meters,  genera- 
tors and  testers  for  shop,  schooU 
Industrial  and  hobby  use. 

e  Scientific  Instruments  ...  In- 
cluding Berkeley  Physics  Lab* 
Mafmstadt-Enke  instrumentation 
for  spectroscopy,  analog  /digital 
•qcjfpment.  pH  meters^  recorders. 

•  Home  Study  Courses  .  .  .  Basic 
kit*courses  in  electronics,  radio, 
and  transistor  theory.  Application 
kit-courses  on  how  to  use  meters^, 
generators,  and  oscilloscopes. 

•  Photographic  Aids  .  * ,  Darkroom 
computers  fof  B  &  W  and  Color 
printing;  electronic  timer:  color 
developing  trays. 

m   Radio    Control    Electronics    .  .  . 

For  modelers.  NEW  Heathkit  R/C 
gear  including  transmitters  and 
receivers  (choice  of  3  bands)  ser- 
vos^ tachometer. 

•  Trail  Bikes  *..  For  off -street 
use,  the  Heathkit  Trail  6(  Snow 
Bike;  outstanding  performance  at 
tow  cost. 

9  Marine  Electronics  . . .  For  safety 
and  pleasure;  radio-telephoneSi 
direction  finders,  depth  sounders, 
weather  monttors,  and  accesso- 
ries. 

m  Automotive  Electronics  ,  .  ,  For 
hobbyist  and  professronal,  new 
Heathkit  3-in*1  Tune-up  Meter, 
Ignition  Analyzer  Scope,  Tachom- 
eter«  accessories. 


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OCTOBER    1969 


■■ 


Extra  Income 

When  people  explain  to  me  that  they  are 
too  short  of  money  to  buy  a  subscription  to 
73  I  look  at  them  in  wonder.  Short  of 
money!  That  is  truly  remarkable  in  this  day 
when  there  are  so  many  simple  ways  of 
making  money  in  spare  time.  The  money  is 
there  for  those  that  axe  willing  to  go  after  it. 
There  are  so  many  things  to  sell  and  so 
many  services  to  offer  that  there  should  be 
something  for  everybody.  If  you  live  in  an 
area  where  you  can  make  unlimited  local 
phone  calls  at  no  extra  charge,  you  have  a 
goldmine.  You  can  sell  products  or  services 
over  the  phone. 

Take  for  instance  selling  magazine  sub- 
scriptions. Most  families  buy  at  least  one 
magazine  subscription  and  some  buy  as 
many  as  a  hundred  a  year*  Why  should  all 
these  people  buy  their  subscriptions  directly 
from  the  magazines  when  they  could  just  as 
well  buy  them  through  you  and  save  money 
for  themselves? 

How  do  you  get  started  in  something  like 
this?  WeU,  first  I  would  write  letters  to  the 
circulation  managers  of  the  larger  circulation 
magazines  on  some  quickly  made  letterhead • 
If  letterhead   costs   too  much,  make  your 
own  with  a  rubber  stamp  on  blank  paper. 
You  can  be  in  business  for  about  $2  as  the 
Amalgamated  Subscription  Agency.  You  can 
find  the  magazine  office  addresses  on  the 
magazine  masthead  at  your  local  newsstand. 
Once    you    have    some    of  those   juicy 
subscription  agent  prices  in  hand  you  can 
start  caOing  people  right  out  of  the  phone 
book  and  quote  them  a  price  on  buying  a 
new  subscription  or  extending  their  current 
subscription     to     Life,    McCalls^    Reader's 
Digest,    etc.    Once    you    get    them    for   a 
customer  you  naturally  keep  track  of  their 
subscriptions    and    give  them   a   call  when 
renewal  time  comes  along*  Ask  them  for  a 
list  of  the  magazines  they  read  and  write  to 


the  other  publishers  too.  Before  long  you 
will  be  an  agent  for  hundreds  of  publishers. 
You  can  find  out  about  special  interests 
locally  too.  Just  as  you  can  get  a  list  of 
customers  from  a  radio  parts  store  which 
will  help  you  sell  radio  magazines,  also  you 
can  get  names  from  a  sporting  goods  store 
for  selling  sporting  magazines,  from  a  camera 
store  to  sell  photography  magazines,  and 
from  the  sports  car  garage  to  sell  car 
magazines.  You  can  buUd  up  lists  of  dozens 
of  special  interests  for  magazine  sales. 

Do  I  have  any  other  money-making  ideas? 
Sure,  plenty-  You're  interested  in  electron- 
ics, so  how  about  seUing  some  electronic 
equipment?  Have  you  ever  thought  about 
selling  closed  circuit  television  installations 
in  your  area?  Many  businesses  and  even 
homes  are  excellent  sales  prospects  for  them. 
Or  how  about  selling  one  of  those  radar 
alarm  systems  to  the  store  owners  locally? 

There  are  thousands  of  things  to  sell.  You 
can  sell  direct  from  your  home,  over  the 
phone^  or  even  act  as  a  manufacturer's 
representative  to  sell  items  to  local  retail 
stores.  The  magazine  Salesmen's  Opportun- 
ity lists  more  products  looking  for  salesmen 
than  you  can  imagine.  The  Macfadden  .50 
book  on  How  To  Make  A  Fast  Buck  will  give 
you  hundreds  of  more  ideas.  Most  of  the 
companies  that  do  pub  he  surveys  are  in  need 
of  help  from  the  hinterlands  and  the  pay  is 
sometimes  surprising. 

One  of  the  biggest  skin  diving  stores  in 
the  country  sprang  from  a  small  bedroom  in 
the  wilds  of  Brooklyn,  The  enterprising  high 
school  student  rubber  stamped  up  some 
letterhead  and  became  a  dealer  for  several 
manufacturers.  Low  overhead  meant  bar- 
gains for  the  customers  and  before  long  his 
parents  were  being  crowded  out  of  the 
house.  Stop  in  and  say  hello  to  Harvey  for 
me  the  next  time  you  visit  Sheepshead  Bay. 
One  of  the  biggest  ham  radio  distributors 
in  the  country  started  out  not  many  years 
ago  in  a  Uttle  comer  of  his  father's  furniture 
store.  Does  that  give  you  any  ideas? 

Wealth? 

A  few  months  back  there  was  a  very  snide 
reference  in  one  of  the  other  ham  magazines 
to  a  little  booklet  I  wrote  a  couple  years  or 
so  back  on  How  To  Make  a  $1,000,000.  Pve 


73  MAGAZINE 


p 


mentioned  this  briefly  in  my  editorials  be- 
fore, I  realize,  explaining  that  my  interest  in 
the  matter  is  more  academic  than  real. 

This  academic  interest  does  lead  me  to 
read  most  of  the  books  that  come  out  on  the 
subject  of  making  money  or  keeping  it,  once 
you've  made  it.  And  that  can  be  a  problem 
too*  In  addition  to  the  book  by  Lloyd 
Colvin  W6KG  on  making  a  million  in  the 
home  construction  business,  I  might  also 
recommend  the  pocket  books  on  The  Rich 
and  The  Super  Rich,  and  Atlas  Shrugged. 
The  first  of  these  was  particularly  interesting 
to  me  because  it  backed  up  my  own  deduct- 
ion that  college  education  not  only  does  not 
help  you  to  make  big  money,  it  in  fact  is  a 
severe  hindrance. 

Fortunately  for  our  school  system  very 
few  people  seem  to  be  even  slightly  interest- 
ed in  going  for  the  big  money.  By  big  money 
I  mean  enough  to  permit  you  to  retire  and 
Mve  comfortably  from  the  invested  capital, 
not  millions  of  dollars. 

Fortunes  are  not  being  made  any  more, 
just  inherited.  However,  thanks  to  inflation, 
it  is  not  at  all  difficult  to  gather  together  one 
little  bitty  million.  This  is  being  done  quite 
frequently  by  those  either  shrewd  enough  to 
figure  out  the  system  or  those  lucky  enough 
to  fall  into  it,  I  suppose  I  should  add  a  third 
group  that  ignore  the  system  and  get  there 
by  stealing. 

Even  considering  Parkinson's  Second  Law 
(expenses  will  always  rise  to  meet  income), 
$1  million  dollars  invested  at  a  mere  5% 
should  last  you  rather  weU,  You  won't  be  a 
big  yacht  customer  or  buy  a  Rolls,  but  at 
$50,000  per  year  the  wife  shouldn't  have  to 
buy  cloth  coats  for  winter. 

Naturally  I  recognize  that  the  preponder- 
ance of  73 's  readers  are  inescapably  com- 
mitted to  their  present  life  and  that  any 
discussion  of  a  career  is,  for  them,  quite 
academic.  On  the  other  hand,  few  of  us  are 
not  occasionally  put  in  the  position  of  being 
able  to  influence  a  younger  person,  so 
perhaps  a  bit  of  thinking  about  careers  and 
the  future  is  not  entirely  out  of  line* 

It  is  aU  too  easy  to  try  to  pass  along  the 
values  that  we  have  been  taught.  1  accepted 
without  hesitation  the  idea  that  everyorie 
that  could  should  go  through  college.  It 
never  even  occurred  to  me  to  question  this.  I 


think  I  have  the  matter  in  better  perspective 
now. 

A  college  education,  complete  with 
Master's  degree,  is  worth  every  dollar  and 
day  to  the  fellow  who  wants  to  work  for  a 
large  company  for  the  rest  of  his  life.  The 
pay  is  good  and  the  Life  is  American  Stand- 
ard, Of  course  it  means  buying  most  of  the 
big  things  on  time  payments  for  many,  many 
years.  The  house  wUl  never  be  paid  for,  since 
advancement  in  business  means  moving  into 
a  bigger  house  every  few  years  with  attend- 
ant refinancing.  Add  car  payments,  boat 
payments,  vacation  payments,  etc.. 

That  Uttle  postcard  from  Cleveland  Insti- 
tute that  we  bind  into  73  every  now  and 
then  got  me  to  thinking-  I  detest  those 
darned  things,  but  as  a  publisher  I  have  to 
recognize  the  economics  of  my  business  and 
run  them  now  and  then.  At  any  rate,  I  sent 
in  one  to  Cleveland  and  in  a  few  days  one  of 
their  nice  four  color  brochures  arrived.  The 
cover  letter  asked  me,  '*Where  do  you  want 
to  be  in  life  in  one  year  ...  in  two  years  .  .  . 
in  three  years  from  now? 

My  own  plans  are  formulated,  but  I 
wonder  how  many  of  the  younger  amateurs 
have  done  much  thinking  about  their  future? 

There  are,  obviously,  many  fortunes  to  be 
made  in  electronics.  It  is  one  of  the  fastest 
growing  fields  in  the  world  today.  This 
means  opportunity.  The  big  corporations 
will  get  bigger,  naturally,  but  thousands  of 
little  companies  will  blossom  out  and  make 
small  fortunes  for  their  entrepreneurs.  The 
little  booklet  that  I  wrote  on  making  a 
million  dollars  explains  a  very  simple 
method  of  taking  advantage  of  this  growth, 
starting  out  with  nothing  and  getting  over 
the  hump  in  a  very  few  years. 

One  does  not  become  a  successful  busi- 
nessman by  starting  his  own  business  any 
more  than  a  concert  pianist  succeeds  by 
going  on  stage  with  no  experience  whatever. 
Success  requires  a  lot  of  hard  work  and  luck. 
And  the  harder  you  work  the  luckier  you 
get. 

Something  else  has  changed  with  the 
generations  too,  I  suspect.  It  may  be  my 
own  special  background,  but  in  my  youth  it 
was  not  looked  down  on  as  a  goal  to  work 
for  wealth.  Now,  when  talking  with  teen- 
continued  on  page  126 


1 


OCTOBER    1969 


3 


Ed  Dusina,  W4NVK 
571  Orange  Avenue  West 
Melbourne,  Florida    32901 


Super  -  Gain 
Antenna  for  40  Meters 


This  article  gives  briefly  the  results  of  a 
study  to  develop  an  antenna  for  the  40 
meter  band  which  would  allow  the  hams  to 
compete  somewhat  better  with  the  foreign 
broadcast  stations  which  practically  take 
over  the  band  in  the  evening  and  ni^ttime. 
In  this  respect  the  study  was  a  partial  success 
in  that  an  antenna  was  developed  based  on 
the  theory  of  super  gain  arrays,  which  rejects 
QRM  from  low  angles.  After  some  experi- 
mental work,  a  super  gain  antenna*  was 
designed  for  the  40  meter  band  which  is 
extremely  simple,  uncritical  and  offers  large 
gain  and  QRM  rejection  factors. 

The  propagation  studies  and  design  work 
for  this  antenna  were  done  at  Dusina  Enter- 
prises in  Melbourne,  Florida. 

Briefly,  the  antenna  to  be  described  has  a 
forward  gain  of  approximately  9  DB  based 
upon  engineering  design  data  developed  in 
the  literature^  and  in  addition  to  the  for- 
ward  gain  has  an  average  of  15  DB  rejection 
against  low  angle  QRM.  Therefore,  two  hams 
both  using  this  type  of  antenna  array  can 
gain  an  advantage  of  about  14  DB^  improve- 
ment in  signal  strength  and  about  1 5  DB  less 
QRM  when  communicating  via  high  angle 
paths  over  short  skip  distances  for  an  overall 
S/N  improvement  of  about  29  DB,  Short 
skip  distances  on  the  40  meter  band  mean 
up  to  about  200  miles  radial  distance  from 
the  transmitter  in  the  daytime  and  up  to 
about  1,000  miles  in  the  nighttime.  These 
distances  are  selected  from  actual  perform- 
ance   measurements    on    the   array    to    be 

described- 

The  antenna  is  of  the  super  gain  class  and 

consists   of  a  single  dipole  antenna  placed 

very  close  to  and  above  a  reflecting  screen 

such  as  to  limit  the  radiation  to  90  degrees 

plus  or  minus  35  degrees  approximately.  The 

antenna  is  made  in  a  very  simple  manner  as 

follows.    A   300  ohm   TV  type   twin  lead 

folded  dipole  is  cut  to  the  length  63  feet  2 


inches  plus  or  minus  1  inch  and  is  fed  in  the 
center  with  RG  58  U  coax  or  some  other  50 
ohm  coaxial  cable.  This  folded  dipole  an- 
tenna is  suspended  tautly  seven  feet  above 
flat  ground  using  three  wooden  poles  or 
some  other  suitable  support  If  metallic 
poles  are  used,  it  is  suggested  that  nylon 
cord  be  used  for  approximately  three  or  four 
feet  between  the  ends  of  the  antenna  and 
the  metal  pole  so  as  to  reduce  the  effect  of 
capacitance  on  the  ends  of  the  antenna.  On 
the  ground  directly  below  this  antenna  are 
laid  three  reflecting  wires  of  a  noncritical 
length  SLxty-five  to  eighty  feet  long.  One 
wire  is  stretched  along  the  ground  directly 
below  the  antenna  element.  One  of  the 
remaining  wires  is  laid  along  the  ground 
parallel  to  the  antenna  but  approximately 
six  feet  from  the  wire  directly  beneath  the 
antenna.  The  third  reflecting  wire  is  placed 
on  the  other  Side  of  the  antenna  such  that 
when  the  reflecting  screen  is  completed 
there  are  three  wires  six  feet  apart,  one 
under  the  antenna  and  one  on  each  side 
forming  a  reflecting  screen  about  eighty  feet 
long  by  twelve  feet  wide.  These  reflecting 
wires  are  laid  on  top  of  the  ground  but  they 
may  be  in  the  ground  if  desired,  A  slightly 
higher  efficiency  will  result  if  they  are 
placed  on  top  of  the  ground,  and  the 
method  used  here  over  a  lawn  was  to  cut  the 
lawn  very  low  and  lay  the  wires  on  top  of 
the  grass.  When  the  grass  grows  back  out,  the 
wires  will  stay  under  the  turf  and  not  be 


63*2*  ti* 


-m 


30Q  TW»N  L€AO 


FOLDED  DtPOLE 


7*0'±3' 


GROUND - 


COAX 


1 


1 


Fig.  1.    Super -gain  40  meter  skywire. 


8 


73  MAGAZINE 


I 


p 


othersome*  The  ends  may  be  wrapped 
around  laige  nails  and  the  nails  driven  into 
the  ground  to  assure  that  the  reflectors  do 
not  curl  up  on  the  ends.  Any  reflector  wire 
size  larger  than  about  No*  26  will  be 
adequate,  and  larger  than  No,  14  is  being 
wastefuL 

As  can  be  seem  from  the  foregoing 
description,     this    antenna    is    sufficiently 

pie  that  every  radio  amateur  can  con- 
struct one.  Although  this  antenna  is  in- 
tended to  be  used  mostly  for  short-range 
communications  up  to  about  200  miles,  due 
to  the  nature  of  the  40  meter  band,  short 
skip  conditions  prevail  much  of  the  time  at 
night  and  the  antenna  is  then  effective  for 
distances  of  1,000  miles  and  sometimes 
more  with  full  gain. 

An  antenna  constructed  in  accordance 
with  the  directions  given  above  yields  the 
following  VSWR  when  fed  with  a  50  ohm 
coaxial  cable.  The  antenna  measured  was  fed 
by  100  feet  RG-58  cable,  used  No.  26  wire 
reflectors  and  was  tested  at  2,000  W  PEP: 

FREQ    7.0    7-1     7.2    7.25     7.3    7.4 

VSWR    3.6    2.6    L3     LOS     1.5    3.0 

Propagation  Effects 

Tests  conducted  in  Florida  on  the  effec- 
tiveness of  tills  antenna  in  improving  com- 
munications capabilities  on  the  40  meter 
band  revealed  significant  improvement  of  an 
amount  unexpected  before  the  tests  were 
made.  These  tests  revealed  the  following 
characteristics: 

Daytime  Use 

Typical  daytime  results  comparing  the 
super  gain  antenna  to  a  two  element  col- 
linear  array  with  2  DB"*  gain  and  elevated 
sixty  feet  above  the  ground  (maximum 
radiation  at  35^  elevation)  gave  the  fol- 
lowing comparisons* 

Stations  from  Alabama  received  at  Mel- 
bourne, Florida,  were  typically  10  DB 
stronger  on  the  60  foot  antenna  than  they 
were  on  the  super  gain  array.  This  communi- 
cation was  at  a  distance  of  about  500  miles, 
which  js  long  skip  (about  35*^  arrival  angle) 
for  daytime  40  meter  conditions.  At  approx- 
imately the  same  time,  stations  in  North 
Carolina,  a  distance  of  about  700  miles,  were 
6  DB  stronger  on  the  high  antenna  than  on 
the  super  gain  array,  while  stations  in  Ten- 
nessee,  approximately   700   mUes  distance, 


c 


FOLDED  OfPOLE 


TO* 


GROUND- 


u 


X 


■80  FT. 

REFLECTORS (3) 


e* 


-«**■ 


J 


SUPCR  GAIN  ARRAr  END  VIEW 

Fifl,  2.  Super  gam  array  end  view, 

were  6  DB  stronger  on  the  high  antenna  than 
on  the  super  gain  array.  The  rejection  drop 
to  6  DB  from  700  mile  distant  stations  was 
due  to  the  loss  of  gain  in  the  collinear  at  the 
25°  arrival  angle  and  not  due  to  improved 
pickup  on  the  super  gain  array  at  the  lower 
angles.  These  data  show  that  the  super  gain 
array  does  in  fact  discriminate  against  signals 
arriving  at  the  lower  elevation  angles.  Com- 
parison checks,  made  at  the  same  time,  on 
stations  transmitting  from  sites  in  Florida 
revealed  that  signals  originating  within  80 
miles  of  the  super  gain  array  were  approxi- 
mately 15  DB  stronger  and  stations  within 
200  miles  were  1 0  to  12  DB  stronger  on  the 
super  gain  array  than  on  the  collinear  array 
at  60  feet  altitude.  In  general,  in  the  daytime 
a  very  marked  increase  in  received  signal 
level  is  apparent  on  any  station  within 
approximately  200  miles  of  the  super  gain 
array,  and  the  most  noticeable  aspect  is  that 
signals  that  are  received  on  the  super  gain 
array  are  much  more  free  from  QRM, 
whereas  on  the  other  antenna  noticeable 
QRM,  or  even  difficult  copy,  may  be 
present.  This  is  a  result  of  the  combination 
effect  of  the  super  gain  antenna  9  DB  gain 
plus  its  1 0  to  15  DB  rejection  capability  for 
low  angle  QRM.  The  15  to  25  DB  improve- 
ment in  signal  to  QRM  is  very  obvious- 
Nighttime  performance 

In  general,  the  super  gain  array  gives 
approximateiy  10  DB  rejection  against  the 
foreign  broadcast  stations  much  of  the  time 
but  some  of  the  time,  due  to  the  nature  of 
the  40  meter  band,  these  long  distance 
signals  arrive  over  many,  many  hops  and 
come  down  within  the  vertical  acceptance 
angle  of  the  super  gain  array.  At  these  times, 
there  is  little  significant  difference  between 
broadcast  interference  received  on  the  high 
collinear  or  the  super  gain  array,  but  the 


1 


OCTOBER    1969 


super  gain  still  boosts  the  transmitted  signal 
greatly.  At  other  times,  when  short  skip  is 
not  predominating,  there  is  a  marked  reduc- 
tion in  QRM  as  well  as  increase  in  signal 
strength  by  the  use  of  the  super  gain  array 
for  communications  out  to  a  distance  of 
approximately  1,000  miles  at  night  Under 
th^e  conditions,  the  strength  for  signals 
originating  within  1,000  miles  is  boosted 
similar  to  that  experienced  over  200  mile 
daytime  paths. 

Most  persons  who  have  worked  with 
array  antennas  on  the  high  frequencies  are 
aware  of  the  fact  that  it  is  difficult  to  get  a 
sixeable  change  in  S-meter  level  between  a 
reference  antenna  and  even  moderate  sized 
array.  However^  the  results  obtained  with 
the  super  gain  array  are  striking  in  that  the 
S-meter  moves  appreciably,  usually  at  least 
one  and  sometimes  two  S-units  in  actual 
signal  level,  and  if  the  QRM  level  wiU  be 
noticed  in  the  quiet  periods  of  the  trans- 
mitting station,  it  will  be  found  to  drop 
from  3  to  5  S-units  when  using  the  super 
gain  array.  If  the  QRM  is  of  low  angle  origin, 
our  experience  has  been  that  this  antenna 
frequently  changes  a  QSO  from  barely  read- 
able to  armchair  quality. 

Due  to  the  extreme  simpHcity  of  this 
antenna  and  to  its  significant  improvement 
in  communications  on  this  particular  band, 
plus  its  small  size,  I  believe  that  if  amateurs 
erect  such  an  antenna  and  test  it  for  them- 
selves, they  win  be  quick  to  see  the  value  of 
it  and  by  this  means  more  use  can  be 
obtained  from  the  40  meter  band.  Partic- 
ularly, this  antenna  woidd  be  an  ideal 
antenna  for  local  nets  or  statewide  nets 
operating  in  the  40  meter  band  in  the 
daytime,  since  it  not  only  greatly  increases 
the  signal  strength  of  the  stations  communi- 
cating, but  significantly  reduces  the  QRM 
leaving  the  state  and  rejects  any  QRM 
coming  in  from  outside  the  state. 

For  those  amateurs  wishing  to  study 
further  on  the  subject  of  super  gain  antennas 
and  the  types  of  gain  that  may  be  obtained, 
perhaps  the  most  understandable  and 
clearly-written  dissertation  is  to  be  found  in 
"Electronic  and  Radio  Engineering"  by 
Terman,  fourth  edition*  Discussions  on  pages 
903  through  908  cover  the  subject  briefly 
and  references   are   given   there   no    more 


theoretical  work  should  one  desire  to  dig 
deeper- 
Many  amateurs  have  from  time  to  time 
used  very  low  dipole  antennas  on  the  40  and 
80  meter  bands  and  some  have  remarked 
that  these  antennas  do  not  perform  as 
poorly  as  they  would  expect  based  on  the 
low  height  These  results,  however,  have 
been  erratic  because  the  effect  achieved  is 
greatly  dependent  upon  the  conductivity  of 
the  ground  under  the  antenna,  and  no 
compensation  was  made  for  the  drastic 
change  in  radiation  resistance  or  the  change 
in  effective  length  for  such  low  antennas. 
The  directivity  gain  of  the  very  low  antenna, 
which  can  be  up  to  eight  times  in  signal 
power,  is  frequently  attained,  in  part,  in  _ 
these  low  installations  over  moderately  con-  ^ 
ducting  ground.  However^  the  counteracting 
loss  in  antenna  efficiency  suffered,  unless  a 
reflecting  screen  is  placed  under  the  antenna 
to  control  the  enormous  losses  in  the 
ground^  the  variable  reflection  distance  and 
low  radiation  resistance  make  the  overall 
results  hi^y  variable  from  one  installation 
to  another. 

The  use  of  the  reflecting  screen  is  very 
important  for  three  reasons.  First,  the  an- 
tenna impedance  will  be  5  0  ohms  only  when 
the  elements  are  cut  as  described  above  with 
reflecting  elements  installed.  Without  the 
reflecting  elements  this  impedance  can  vary 
significantly.  Secondly,  the  efficiency  of 
drop  well  below  5  0  percent  in  most  installa- 
tions without  this  reflecting  screen.  This 
means  that  the  overall  gain  of  the  antenna 
may  be  anywhere  from  zero  gain,  or  perhaps 
even  a  loss,  to  a  full  9  DB  gain,  depending 

upon  the  peculiarities  of  the  soil  under  the 
antenna.  Thirdly,  without  the  screen  the 
spacing  between  antenna  and  image  is  un- 
known and  unstable,  varying  with  ground  . 
conditions.  Due  to  the  utter  simplicity  of  ^ 
the  reflecting  screen,  it  is  not  worth  the  risk 
to  omit  it*  Also,  the  effective  length  of  the 
antenna  varies  with  ground  conductivity 
without  the  screen,  so  design  becomes  a  cut 
and  try  affair* 

It  is  hoped  that  other  amateurs  will  erect 
^milar  antennas  and  mn  comparative  tests 
on  40  meters  as  well  as  80  meters  and  160 
meters.  The  80  meter  band  performance  of 
the  super  gain  array  has  not  been  explored 


10 


73  MAGAZINE 


p 


yet  so  that  the  relative  percentage  of  the 
time  during  which  short  skip  conditions 
prevail,  and  therefore  the  magnitude  of 
improvement  possible,  is  unknown  to  me  at 
this  time,  but  will  be  published  as  soon  as 
my  tests  are  completed.  However,  those 
wishing  to  try  such  an  antenna  on  80  meters 
or  160  meters  may  scale  the  dimensions 
given,  which  is  centered  on  7250  khz,  to 
obtain  the  design  numbers.  For  those  with 
lots  of  room,  a  group  of  these  units  oper- 
ating broadside  could  generate  a  formidable 
signal  indeed,  but  more  than  about  four 
units  would  begin  to  restrict  coverage 
noticeably.  .  .  .  W4NVK 

*  Patent  disclosure  fifed, 

^a-'*Maximum    Directivity    of   an   Antenna," 
H,  J,  Riblet,  Pioc,  IRE,  36  p  620,  May,  1948- 

b.  T,  T,  Taylor,  Proc.  IRE,  26  p  1 135,  Septem- 
ber, 1948, 

c.  "Physical  Limitations  of  Directive  Systems," 
t.  J.  Chu,  J.  Apl.  Phys.,  19  p  1163,  Decem- 
ber, 1948 

d.  "Directional  Antennas,"  G.  H.  Brown,  Pioc. 
IRE,  25  p  122,  January,  1937, 

^This  figuie  is  referenced  to  a  dipole^  all  others 

in  this  artkle  are  referenced  to  isotropic- 
^Reference  to  dipole. 

Printed  Circuit  Soldering  Aid 

Fixing  printed  circuits  is  really  quite 
simple.  Just  clip  out  the  defective  com- 
ponent, leaving  as  much  lead  on  the  board  as 
possible,  and  solder  the  new  component  to 
the  old  leads.  This  method  works,  and  is 
recommended  by  many  authorities.  It  does 
look  like  a  butcher  job  though,  doesn't  it?  A 
much  better  way  which  doesn't  take  much 
more  time,  considering  the  time  spent  locat- 
ing the  defective  component ,  is  to  take  it 
out  completely.  Usually  the  holes,  whether 
printed  through  or  eyelets,  are  plugged  up 
with  the  old  solder*  Let  it  cool  off;  then 
quickly  reheat  and  clean  the  holes  with  a 
piece  of  piano  wire  or  stainless  steel  wire 
about  *050  inch  diameter.  Solder  wiU  not 
stick  to  it,  yet  it  can  be  formed  and  filed  to 
a  sharp  edge  at  one  end  to  aid  in  cleaning 
out  the  fringes  of  solder.  A  bit  of  masking 
tape  makes  a  convenient  handle  if  wrapped 
around  the  center  portion  of  the  tool- 
Roy  A.  McCarthy,  K6EAW 


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DIVISION  OF  AEROTRON,  INC 

p.  0.   BOX  6527  •   RALEIGH   N,  C.  27608 


I 


OCTOBER    1969 


11 


DX  Corner 


Dave  Mann,  K2AGZ 
One  Daniel  Lane 

Kinnelont  New  Jersey  07405 


A  number  of  letters  have  come  in  from 
WTW  Certificate  holders  asking  me  to  cor- 
rect errors  in  the  standings  hst  published  in 
March.  While  there  isn*t  a  lot  that  we  can  do 
about  the  list  already  published,  every  effort 
will  be  made  to  see  that  future  boo^oos  are 
kept  to  a  minimum.  Bear  with  me  and  1  am 
sure  that  it  will  all  be  straightened  out. 

The  cards  that  have  been  coming  in  show 
that  20  meters  is  still  the  favorite  DX  band. 
But  there  are  signs  of  increased  activity  on 
the  other  bands.  In  the  last  few  weeks  Fve 
been  pleased  to  see  that  cards  have  been 
submitted  for  awards  on  two  and  even  three 
bands,  I  realize  that  many  of  you  are  chasing 
that  elusive  300  mark  on  20,  but  you  should 
do  a  bit  of  listening  on  others.  The  results 
may  prove  gratifying.  You  will  find  that  a 
great  many  DX  stations  will  be  eager  to 
make  schedules  for  the  other  bands  as  well, 
for  they  are  also  interested  in  contacts  on 
more  than  one  band. 

We  have  gotten  used  to  thinking  of  DX  in 
terms  of  15-20  meters,  principally.  A  com- 
mon complaint  goes  something  like  this,  "I 
listened  for  a  couple  of  hours  on  10  meters 
the  other  night  and  the  band  was  completely 
dead.  There^s  notliiiig  doing  there." 

Td  like  to  suggest  that  you  aim  your 
antenna  over  the  pole,  about  345  degrees 
here  in  the  East,  and  call  CQ  DX  Pacific  a 
few  times,  I  don't  want  to  make  any  rash 
predictions,  but  don't  be  surprised  if  you  get 
answers  from  VR,  J  A,  DU,  XW8,  VS6  and 
the  like.  It  seems  that  a  lot  of  people  are 
listening  at  the  same  time  without  calling.  So 
nobody  answers! 

rd  also  like  to  encourage  you  to  spend 
more  time  on  75-80  meters.  There  have  been 
some  very  good  openings  lately,  and  would- 
n't it  be  nice  to  hang  a  certificate  on  the  wail 
for  this  band?  How  about  it?  In  line  with 
rd  like  to  suggest  that  if  you  have  not 


gotten  your  copy  of  the  73  DX  Handbook, 
you  do  so  at  your  earliest  convenience. 
Concerning  my  mention  of  80  meters,  there 
is  a  tremendous  article  in  the  Handbook  on 
just  this  subject  by  John  Devoid  ere  0N4UN- 
It  is  complete  in  every  detail.  John  really 
went  all  out  on  this  one,  I  am  confident  that 
anyone  who  reads  and  absorbs  it  will  acquire 
valuable  information  that  will  assist  in  gar- 
nering many  DX  contacts  on  this  band* 

So  I  hope  you  will  order  this  very 
important  book  soon.  If  you  are  interested 
in  DX,  I  can  assure  you  that  it  is  the 
smartest  three  bucks  you  could  spend,  and 

worth  many  times  the  price, 

IVe  been  thinking— there  are  quite  a  few 

persons  on  the  air  who  express  anti-DX 
sentiments  wliich  often  go  unchallenged. 
There  seems  to  be  an  idea  going  around  that 
DX  fever  is  an  indication  that  somehow  a 
ham  is  not  a  gentleman.  It  is  a  bit  reminis- 
cent of  the  attitude  of  some  of  my  dry  fly, 
purist  angler  friends  toward  bait  fishermen. 

ThiSj  of  course,  is  arrant  nonsense.  My 
only  reason  for  bringing  it  up  at  all  is  that 
rd  like  some  of  these  DX  haters  to  try  it  for 
themselves,  just  once.  Let  them  get  into  the 
competition  for  a  piece  of  rare  DX,  over- 
coming their  prejudice  for  just  that  brief 
recess,  for  just  a  taste  of  it.  I'll  warrant  that 
a  majority  of  them  will  be  forced  to  concede 
that  they've  had  the  time  of  their  lives. 

It's  hard  to  admit  one  basic  truth.  All 
types  of  operation  may  flourish  and  flower 
without  adversely  affecting  the  organic  well- 
being  of  ham  radio  as  a  whole.  There  are 
some  who  express  fear  for  the  hobby^s 
future  unless  everyone  throws  out  his  com- 
mercially buUt  gear  and  builds  his  own.  Silly, 
isn't  it?  Traffic  men  despise  ragchewers.  CW 
operators  have  contempt  for  phone  men  and 
vice  versa*  QRP  enthusiasts  loathe  high 
powered  boys.  AM'ers  call  SSB*ers  names^ 


12 


73  MAGAZINE 


p 


p 


r 


Linear  Linear  Amplifier 

All  amplifiers  for  SSB  operation  are  called  linear 
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linear  linear.  You've  heard  the  clean,  sharp  signals 
on  the  air.  They  shout  "LINEAR  LINEAR". 
As  proof,  study  the  oscilloscope  displays  published 
in  a  national  amateur  publication  which  reviewed 
the  2K  in  comparison  with  competitive  amplifiers. 
Note  the  2K*s  classic  straight  slope  bow-tie  pattern 
in  figure  A  as  compared  with  the  non-linear  curv- 
ature of  the  competitive  amplifier  in  figure  B. 
Remember... the  curvature  of  figure  B  means 
"splatter"  on  the  band.  Remember.. .the  straight 
lines  in  figure  A  are  the  sharp,  clean  signals  of  the 


Figure  A 


Figure  B 


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OCTOBER  1969 


13 


I 


and  low  band  ops  wouldn't  spit  on  VHF*ers, 
And  so  it  goes.  The  fact  is,  we  all  need  each 
other,  for  the  very  life  blood  of  ham  radio  is 
its  broad  diversification •  We  need  all  types  of 
operations  on  all  our  frequencies. 

Since  DX  occupies  the  hearts  and  minds 
of  a  large  segment  of  our  ham  population,  I 
believe  it's  wrong  for  non-enthusiasts  to 
express  violent  opprobrium  on  the  air,  as 
though  they  were  talking  about  lepers. 

Many  of  our  critics  became  sour  on  DX 
because  they  were  not  successful  at  it.  They 
probably  discovered  that  it  was  not  as  easy 
as  they  thought.  Successful  DX'ing  is  one  of 
the  most  demanding  facets  of  the  game, 
calling  for  skill  and  patience,  coupled  with 
experience  and  maturity.  It  is  not  unusual  to 
chase  a  specific  country  for  years,  and  even 
then^  there  is  no  guarantee  of  getting  it,  I 
have  been  after  a  few  of  them  for  a  long 
time,  and  I  scrutinize  the  bands  for  them 
almost  every  time  I  sit  down  to  operate.  This 
is  the  only  way  I  know;  there  is  no  royal 
road  to  success. 

Many  stations  not  engaged  in  DX  chasing 

are  operated  in  a  fashion  that  would  make 

the  average  DX'er  cringe.  They  use  mediocre 
antenna  systems  which  simply  could  not  cut 

the    mustard.   Their   procedures  would  not 

begin  to  serve  in  DX*ing,  for  they  still  do  not 

comprehend    the    importance    of   listening, 

listening,  and  listening  some  more.  They  are 

far  too  busy  saying  their  "By  GoUy*'  and 

"Fine  Business"  for  that. 

But  this  is  only  one  man's  opinion,  Don^t 
take  my  word  for  it.  If  you  want  to  get  a 
taste  of  real  excitement ^  put  your  signal  and 
skill  on  the  Une,  and  get  into  one  of  the 
pile-ups  sometime.  You  may  become  frus- 
trated, that's  for  sure.  But  you  wiU  also  find 
yourself  developing  a  healthy  respect  for  the 
skill  and  ability  of  the  successful  ones. 

We  all  recall  the  story  of  the  completely 
outfitted  fisherman,  with  all  the  fancy 
tackle,  encountering  the  kid  with  the  buggy 
whip,  dime  store  hook  and  can  of  worms. 
The  urchin  has  no  fancy  flies,  no  two 
hundred  buck  rod,  no  waders,  no  nothing. 
But  he  has  a  stringer  full  of  fish,  and  the 
fancy  dude  with  the  high  class  equipment 
hasn*t  a  single  trout.  AU  the  kid  has  is  plain 
old  talent,  that's  all!  There's  a  lesson  there 
for  the  would-be  DX'ers, 


Well,  that*s  all  I  intend  to  say  on  the 
subject.  If  you  are  against  DXMom,  and  you 
have  a  feeling  of  superiority  over  the  fools 
who  participate  in  it,  why,  you  go  right 
aliead  and  do  your  rag-chewing  or  whatever. 
It  will  be  your  loss,  I  know. 

*i^L|  a^j  ^^  ^b 

^P*  ^P  ^m*  ^k 

I  worked  an  odd  one  the  other  evening  on 
14  mhz  CW.  There  was  a  huge  pUe-up  on  the 
low  end  caUing  LG5LG.  He  claimed  to  be 
operating  from  the  Independent  Territory  of 
Morokuiien,  on  the  Norwegian -Swedish  fron- 
tier. He  gave  his  QSL  address  as  LA4YF,  and 
asked  for  three  IRC's.  Well,  though  I  have  a 
very  suspicious  nature,  I  have  a  standard 
procedure  for  cases  that  seem  phoney.  I 
work  *em  first  and  ask  questions  afterward. 
So^  I  got  the  contact^  hurdling  the  first 
obstacle, 

I  must  admit  to  curiosity,  so  I  began  to 
investigate  Morokuiien.  I  consulted  four  of 
the  best  atlases  ever  printed,  and  there 
wasn*t  a  trace  of  the  place  in  any  of  them. 
By  this  time  I  was  pretty  certain  it  had  been 
a  counterfeit  call,  used  by  some  joker,  trying 
to  have  some  fun  and  excitement  for  him- 
self. 

Later  that  night,  however,  1  hooked  up 
with  a  Swedish  ham  who  told  me  that  there 
really  is  such  a  place,  and  that  LG5LG  is  a 
legitimate  operation.  He  further  informed 
me  that  the  IRC's  are  redeemed,  and  the 
funds  are  turned  over  to  a  crippled  children's 
hospital  and  therapy  center.  Needless  to  say, 
I  sent  my  QSL  out  the  next  morning. 

Both  the  SM  and  1  agreed  that  it  would 
be  extremely  unlikely  that  this  LG5  would 
count  for  a  new  country,  but  today,  when 
national  boundaries  and  political  status  is  in 
a  constant  state  of  flux,  you  can  never  teU, 
Incidentally,  he  also  said  that  operations 
from  Morokuiien  are  very,  very  rare,  so  there 
is  not  likely  to  be  another  operation  there  in 
a  long  while.  So,  if  you  hear  him,  don't  turn 
up  your  nose.  Get  the  contact,  just  in  case* 
What  have  you  got  to  lose? 

Gus  has  been  making  all  sorts  of  stops  in 
the  Indian  Ocean  area,  but  so  far  there*s 
been  nothing  that  would  add  to  anybody's 
totals,  either  for  WTW  or  DXCC.  It's 
pleasant  to  work  Gus  anyway,  of  course,  but 
it  would  sure  be  nice  to  hear  him  from  some 
rare  one,  Sikkim,  Bhutan,  Tibet  or  maybe 


14 


73  MAGAZINE 


r 


BY  land-  Speaking  of  rare  ones,  Tra  pre- 
paring a  questionaire  for  publication  in  the 
near  future ^  which  will  aid  in  determining 
the  priority  ratings  of  wanted  countries.  We 
will  then  be  in  a  position  to  assist  DXpedi- 
tioners  to  plan  their  itineraries.  It's  not  that 
we  spurn  a  country  simply  because  we 
already  have  it  in  our  logs,  but  all  of  us  are 
itching  to  get  a  shot  at  some  of  the  more 
elusive  ones,  Tm  sure.  Is  there  anyone  who 
wouldn^t  jump  at  the  chance  to  work  a  ZA, 
YI^  F08  Clipperton,  etc.?  The  questionaire 
will  appear  in  a  few  months,  and  when  you 

get  your  73,  don't  forget  to  fiU  the  thing  out 
and  send  it  in,  so  we  can  tabulate  some 
meaningful  country  priorities* 

The  1N2A  that  showed  up  on  20  Meters  a 
short  time  ago  has  to  be  a  phoney.  The 
prefix  is  not  assigned  by  ITU,  and  the  Marco 
Island  he  purported  to  operate  from  is  not 
listed  in  any  of  the  four  major  atlases  which 
I  consulted,  I  cannot  find  any  island  in  the 
area  of  coastal  Peru  which  might  be  the  one, 
for  all  those  shown  have  well  established 
names.  Oddly  enough^  the  signals  peaked  at 
approximately  the  right  beam  heading.  My 
best  guess  is  that  someone  was  operating 
someplace  in  Ecuador,  Peru  or  Chile, 

I  heard  another  lulu  the  other  morning^ 
claiming  to  be  in  Basra,  Iraq,  He  was  using 
G3N0F/YI  and  called  himself  Mike,  The 
only  catch  is^  G3N0F  is  Don  McLean,  a  very 
good  friend  of  mine  in  Yeovill,  who's  more 
interested  in  jazz  recordings  than  in  traveling 
for  an  oil  company^  which  this  joker  claimed 
to  be  doing. 

I  simply  can't  understand  the  type  of 
mentality  which  goes  to  the  trouble  of 
engineering  a  DX  hoax.  It's  a  lot  of  hard 
work;  almost  drudgery.  And  .  .  -  for  what?  I 
think  that  most  of  these  guys  must  suffer 
from  vacant  apartments  in  the  upper  story s. 

Here's  something  that's  bothered  me  for  a 
long  time.  You  hook  up  with  a  German, 
Czech  or  Russian.  He  speaks  the  English 
language  with  an  accent,  that^'s  for  sure.  But, 
have  you  ever  noticed,  as  I  have,  that  his 
grammar  is  perfect  in  most  instances.  Syn- 
tax,  number,  gender  and  case  are  used 
properly.  He  never  says  who  when  he  means 
whom*  He  doesn't  mix  up  imply  and  infer. 
He  doesn't  split  infinitives  either.  Yet,  Amer- 
ican   amateurs,    born    and    reared    in    this 


country  J  sometimes  speak  the  most  horren- 
dously  poor  English  to  be  heard  anywhere. 
It  is  doj^nright  humiliating  to  hear  some  of 
the  lingo  that  passes  for  English.  As  my 
friend  W2NDK,  Arthur  Harris,  says,  "He 
don't  speak  so  very  many,  but  he  doing  the 
best  what  he  are!" 

I  heard  a  couple  of  lads  on  20  the  other 
night  who  were  having  a  time  for  themselves. 
They  kept  reducing  power  to  see  how  long 
the  copy  would  hold  up.  The  fellow  in 
Australia  was  audible  here  in  New  Jersey 
when  he  was  reporting  a  dc  input  of  500 
miliwatts,  I  lost  the  Ohio  station  at  about  75 
watts,  but  the  VK  continued  to  read  him.  It 
was  most  interesting,  I  understood  why  the 
VK  came  through  so  well  when  he  described 
his  antenna.  He  was  using  a  wire  quad; 
eleven  elements  on  a  1 50  foot  boom.  I  can't 
even  visualize  an  antenna  like  that.  Brother, 
that's  what  you  call  an  aerial  and  a  half! 

During  the  course  of  the  last  year  or  so  I 
have  been  QSL  manager  for  Danny  Willis, 
CT2AS.  It  is  really  surprising  to  see  so  many 
hams  who  are  still  unaware  of  the  impor- 
tance of  getting  the  date  correct,  and  making 
sure  that  the  contact  is  logged  in  CMT. 
There  simply  isn't  enough  time  in  which  to 
go  hunting  through  hundreds  of  log  entries 
in  order  to  find  one.  It^s  the  proverbial 
needle  in  the  liaystack.  Please,  everybody, 
get  into  the  habit  of  using  Zulu  time* 

We  have  finally  gotten  the  new  countries 
lists  for  WTW  from  the  printer,  and  they  are 
ready  to  be  sent  out  to  anyone  who  requests 
them.  Remember,  you  will  need  one  for 
each  of  the  bands  you  intend  to  submit  for, 
but  they  need  not  be  sent  in  with  your 
cards.  You  may  transcribe  the  list  on  ordin- 
ary paper,  typewritten,  if  possible,  showing 
the  contact  and  date.  So  long  as  this  list  is 
legible  it  wUl  suffice. 

Here  are  the  currently  claimed  WTW 
scores.  Some  of  you  have  been  inquiring 
about  countries  lists.  They  are  in  preparation 
and  should  be  availably  soon.  All  who  have 
requests  in  for  them  will  receive  them  as 
soon  as  they  come  off  the  press. 

It  looks  like  we  are  close  to  our  first 
WTW-300  certificate.  Vd  feel  a  lot  better  if 
there  were  some  hot  competition  for  this 
award.  Many  of  you  have  evidently  been 
lying  "doggo"  recently,  for  I  have  not  been 


i 


OCTOBER    1969 


15 


getting  too  many  revised  claimed  scores 
lately.  How  about  pumping  up  those  scores? 
Frankly,  WTW  is  hurting  from  a  drought  of 
activity.  There  does  not  appear  to  be  suf- 
ficient interest  in  the  award  at  present,  and 
the  reasons  for  this  may  be  many  and  varied. 
Not  the  least,  I'm  sure,  is  the  removal  of 
some  of  the  frequencies  formerly  enjoyed  by 
all  of  us.  Rather  than  probe  into  those 
reasons,  though,  let's  just  say  that  we  hope 
the  inactivity  is  merely  temporary,  and  that 
we  can  look  forward  to  better  conditions 
ahead.  Tm  pretty  sure  that  if  a  rare  one  were 
to  show  up  there  would  be  a  revival  of 
interest.  All  we  need  is  a  Clipperton  opera- 
tion; Tokelaus^  Chagos,  Agalega,  Kuria 
Muria,  or  the  like^  and  watch  those  grounded 
grid  amplifiers  start  heating  up-  The  Malpelo 
action  recently  showed  that  there*s  still  lots 
of  life  among  the  DX  hounds. 

The  Coast  Guard  has  now  revised  its 
former  opposition  to  operations  on  Navassa, 
They  will  now  permit  ham  operations  there 
during  the  two  times  a  year  that  a  Coast 
Guard  vessel  in  in  the  vicinity.  This  is 
excellent  news,  for  there  are  many  who  have 
expressed  a  strong  desire  to  go  there.  So  I 
think  that  we  can  all  look  forward  to 
another  shot  at  this  goodie  in  the  near 
future. 

WTW  HONOR  ROLL  (claimed  scores) 

7  mhz-CW: 

W4BYB  151 

W3WJD  100 

W8ZCK  100 

VE3BLU  105  (new  certificate) 


14  mhz-CW: 

WB6NWW 

113 

K4CEB 

102 

W8EVZ 

102 

W4CRW 

101 

WA2DIG 

100 

K8IKB 

100 

WB6SHL 

100 

W9HFB 

100 

W50DJ 

100 

WB2TK0 

100 

WA9KQS 

100 

WIETV 

100 

K5BXG 

100 

K4ASU 

100 

WA6GLD 

100 

W2UGM 

100 

14  mhz-Phone: 

W6YMV 

150 

K2Q0U 

125 

WB2NSG 

122 

K4GX0 

120 

KISHN 

WISEB 

W4TRG 

WA40PW 

SV0WL 

W0SFU 

W3SEJ 

CN8FC 

VE3ELA 

VE6AKV 

K4VKW 

W60HU 

W8WAH 

WA0OAI 

21  mhz-CW: 

W40PM 

W0DAK 

WA9NSR 

WB2UDF 

VE6TP 

WA6GLD 

W0RRS 

WA90TH 

21  rrihz-Phone: 

W40PM 

WA5L0B 

W6MEM 

WA2FQG 

WAIEUV 

WA5DAJ 

W9NNC 

WB2RLK 

W8WRP 

W4SYL 

W2PV 

WIEED 

K5HYB 

W2VBJ 

K4VKW 

WB20B0 

K9PPX 

W6YMV 

WA4WTG 

WA0OAI 

WA8VFK 

28  mhz-Phone: 

WAS  LOB 

W6MEM 

WA5DAJ 

WB2RLK 

W2PV 

W2VBJ 

WA7BPS 

W4GJ0 

W5YPX 


111 

110 
106 
105 
105 
104 
103 
103 
102 
102 
102 
101 
101 
101 


200 
07 
03 
00 
00 
00 
00 

100 


220 
62 
61 
55 
38 
30 
25 
10 
06 
06 
04 
03 
01 
01 
01 
01 

100 
00 
00 
00 
00 


50 
29 
17 
15 
106 
04 
02 
00 
00 


We  are  in  need  for  check  points  in  the 
1st,  4th  and  the  10th  districts.  Also  any 
clubs  on  the  continent  of  Europe,  South 
America  and  Africa  wanting  to  take  on  this 
job,  please  get  in  touch  with  me  through  the 
magazine  or  direct,  if  you  would  like  to 
help. 

Here  is  a  list  of  all  current  check  points. 
We  still  need  three  more  to  fill  out  the  roster 


16 


73  MAGAZINE 


Call 


State  . 


3  years    ZIP 
t  year 


^^N^^^^I^^^N^M^I^^^^^^Il^W 


Special  CHAR 
#r  SUBSCRIP" 


RADIO  TODAY  is  for  the  CB'er 

Tests  of  the  newest  equipment,  reviewed 

by  fellow  CB'ers,  gadgets,  accessories,  anten- 
nas, test  equipment,  everything  you  want  to 
know  about.  How  things  work  „  .  how  to 
hook  them  up  .  .  .  how  to  use  them  .  .  .  their 
limitations  .  -  ,  their  advantages  ...  all 
straight  from  the  shoulder  with  no  punches 
pulled.  If  it  has  anything  to  do  with  CB  and 
is  for  sale  in  finished,  kit  or  surplus  form, 
you  will  read  about  it  in  detail  in  Radio  To- 
day; 

RADIO  TODAY  is  for  SWL^s 

Tests  on  every  possible  piece  of  radio 
equipment  of  interest  to  the  SWL.  Listening 
on  VLF,  medium  waves,  broadcast  band, 
short  waves,  pohce,  fire,  forestry,  weather 
bureaus,  satellites,  space  ships,  microwaves, 
amateurs,  aircraft,  doctors,  taxis,  telephone 
services  •  .  .  or  tuning  in  radio  Teletype 
weather,  news,  stock  market,  foreign  lan- 
guages ...  or  facsimile  weather  maps  and 
even  the  Tiros  satellite  direct!  If  it  is  equip- 
ment used  for  listening  .  <  ,  an  accessory  or 
gadget,  you  wiU  read  about  it  in  Radio  To- 
day. 

RADIO  TODAY  is  for  the  Radio  Controller 
Read  about  every  available  piece  of  eq- 
uipment, accessory,  test  equipment,  etc.,  of 
interest  to  the  RC'er.  We  will  cover  control 
of  model  planes,  cars,  boats  .  .  .  and  even  re- 
mote control  of  radio  stations. 


RADIO  TODAY  is  for  the  Novice  Amateur 
Radio  is  one  of  the  greatest  hobbies  there 
is  today.  There  is  fun  in  CB  .  ,  ,  fun  in  SWL 
...  in  RC  .  .  .  and  even  more  fun  in  amateur 
radio ,  ,  .  being  able  to  talk  around  the 
woyid.  Radio  Today  will  help  you  enter  the 
world  of  amateur  radio  tlirough  a  Novice  Li- 
cense. RADIO  TODAY  is  written  for  the 
average  person,  not  the  technician  or  the  en- 
gineer. 

It  isn't  necessary  to  use  highly  technical 

language  to  explain  how  to  buy,  hook  up 

and  use  commercially  available  equipment. 

Join  in  the  fun  of  radio  by  subscribing  to 

Radio  Today. 

The  regular  subscription  rate  will  be  $5 
for  one  year  with  monthly  publication  to 
start  late  this  year.  Charter  subscribers  may 
subscribe  for  only  $4  for  the  first  year.  Give 
RADIO  TODAY  a  try.  Send  in  your  CHAR- 
TER Subscription  today. 

All  Charter  Subscribers  wiU  receive  a 
Special  CHARTER  SUBSCRIBER  CARD 
which  will' be  extremely  valuable  later  on. 
Don't  miss  this  opportunity •  Don't  miss  that 
first  big  (and  rare)  first  issue. 


w 


Regularly 

One  Year $5 

Three  Years  .  -$10 


SPECIAL 

$4 
$8 


i 


I 


OCTOBER    1969 


17 


and  I  wish  some  clubs  and  groups  would 
volunteer  to  complete  our  list.  Meanwhile  if 
your  area  is  not  covered,  send  cards  directly 
here,  at:  1  Daniel  Lane,  Kinnelon,  NJ 
07405,  along  with  $1.00  to  cover  handling 
and  cost  of  certificate,  etc.  If  you  wish  your 
cards  to  be  returned  via  registered  mailj  etc., 
be  sure  to  enclose  enough  money  to  cover 
same,  otherwise  they  will  be  returned  at  the 
cheapest  rate;  hardly  the  safest  method. 


1st  District 


None  (send  cards  here) 


2nd  District         Peninsula  Amateur  Radio  Club 
Foot  of  25th  St.,  Veterans  Park 

Bayonne,  NJ  07002 

3id  District         Western  Pennsylvania  DX  Society 
John  F.  Wojtkiewicz  W3GJY 
1400  ChapUn  St. 
Conway,  PA  15027 

4th  District         None  (send  cards  here) 

5th  District         Garland  Amateur  Radio  Cluti 
2905  Sheridan  Drive 
Garland,  TX  75040 

6th  District         Orange  County  DX  Club 
James  N,  Chavarria 
3311  Steams  Drive 
Orange,  CA  92666 

7th  District         Western  Washington  DX  Club 
WiUiam  H.  Bennett  W7PH0 
18549  Normandy  Terrace  S,W- 
Seattle,  WA  98166 

8th  District  Straits  Area  Amateur  Radio  Club 

William  Moss  WA8AXF 
307  Grove  Street 
Petoskey.  Ml  49770 

9th  District  Montgomery  County  Amateur  Radio 

Club 
Scott  Millick  K9PPX 

Litchfield^  IL  62056 

10th  District       None  (send  cards  here) 

Canada  (all)         Edmon  ton  DX  Club 
VE6GX,  12907  136th  Ave. 
Edmonton,  Alberta,  Canada 

Oceania   New  Zealand  Assn,  of  Radio  Transmitters 

Jock  White  ZL2GX 
152  Lytton  Road 
Gisborne,  New  Zealand 

South  America    Venezuela  Amateur  Radio  Club 
PO  Box  2285,  Attention  YV5CH0 
Caracas,  Venezuela 

Vs  you  can  see,  we  are  badly  in  need  of 
idditions  to  this  list  in  Europe,  Africa, 
Jouth  America  and  Asia.  We  could  also  do 
¥ith  one  in  Australia,  Interested  groups  and 


clubs  please  contact  me  via  73  magazine  or 
direct. 

I  take  parficular  pleasure  in  announcing  a 
welcome  addition  to  our  award.  The  Com* 
mittee  has  agreed  that  we  should  establish 
two  new  categories.  Here  is  the  rundown, 

MWTW,  Mobile  Worked  the  World,  is 
awarded  to  mobile  stations  exclusively.  The 
one  bandone  mode  rule  is  bypassed  for  this 
category.  All  bands —all  modes  will  count 
toward  the  certificate.  The  only  stipulation 
is  that  any  contact  must  be  made  with  a 
mobile  antenna.  We  will  not  honor  any  QSO 
known  to  have  been  made  where  a  mobile 
rig  was  piped  into  a  fixed  station  aerial,  as  is 
sometimes  done  on  vacation  trips, 

WTWM,  Worked  the  Worid  Mobile,  is 
awarded  to  fixed  stations  for  contacts  with 
mobiles,  including  maritime  and  aeronaut- 
ical. In  this  category  we  will  retain  the  one 
band-one  mode  rule.  All  other  WTW  rules 
will  continue  to  apply,  with  respect  to  date 
of  contact,  etc. 

After  some  thought/ it  has  been  decided 
that  cards  which  may  already  have  been 
submitted  and  counted  toward  an  existing 
certificate,  may  be  applied  to  the  new 
MWTW  award.  If  you  decide  to  go  for  this 
certificate,  you  may  re-submit  any  of  them 
wliich  might  be  eligible  for  inclusion.  But, 
please  make  sure  to  note  that  they  are 
re-submissions  so  that  we  have  a  record  in 
your  file. 

We  don't  have  the  new  certificates 
printed  for  these  awards  as  yet,  but  you  may 
submit  the  cards  now.  We  will  process  them 
now  and  notify  you  at  once,  sending  the 
certificates  as  soon  as  we  get  them.  Please 
send  your  entries  to  me,  direct,  as  the  check 
points  have  not  yet  been  notifi^  of  the  new 
awards.  Good  luck  to  aU  participants. 

We  will  not  issue  new  certificates  for 
credits  above  200.  Instead,  we  have  designed 
an  endorsement  sticker,  which  is  to  be 
affixed  to  the  original  award.  Any  applicant 
for  WTW-100  or  WTW-200  will  receive  the 
certificate,  and  when  he  applies  for  300  he 
will  be  awarded  the  endorsement. 

This  will  save  us  a  great  deal  of  trouble 
and  expense^  and  it  will  save  you  the  cost  of 
an  additional  display  frame.  Also,  it  wiU 
enable  us  to  send  you  back  your  QSL  cards 
plus  the  sticker  in  one  mailing  rather  than 


8 


73  MAGAZINE 


two.  It  win  also  do  away  with  the  problem 
of  mailing  tubes,  which,  I  swear  to  yon,  is 
the  biggest  pain-in-t he-posterior  I  have  ever 
encountered.  You  cannot  buy  less  than  a 
gross  of  the  bloody  things,  and  when  you  do 
get  them  you  have  to  find  adequate  space  to 
put  them.  And,  they  collect  more  dust  than 
you  could  imagine,  but  worse  than  that, 
they  seem  to  be  a  natural  habitat  for 
honey-mooning  field  mice,  wasps,  spiders, 
carpenter  ants  and  other  unattractive  var- 
mits  of  varying  descriptions. 

There  may  be  a  few  recently  issued 
certificates  whose  holders  are  not  listed  this 
time.  They  will  be  included  in  the  next 
publication  of  the  list. 

Next  time  we  hope  to  have  a  report  from 
Gus.  Also  may  have  some  interesting  dis- 
closures from  a  well  known  former  DXpedi- 
tioner  who  will  tell  all  about  some  of  his 
past  corner  cutting.  This  promises  to  open 
up  a  whole  can  of  beans,  and  is  guaranteed 
to  turn  a  few  faces  red. 

Next  issue  will  include  updated  claimed 

scores,  new  certificates  issued  and  order  of 

standings.     Don't    forget    about    the    new 

MWTW  and  WTWM.  Vd  Uke  to  see  lots  of 

applications  in  the  mailbox.  That's  it  for 

now.  See  you  next  month. 

.  .  .  K2AGZ 


Try  This  One 

Try  tiiis  one  on  your  friends  and  see  how 
many  will  take  the  bait  without  giving  it  a 
second  thought.  The  problem  is:  Your  moni- 
tor scope  has  gone  sour.  The  trace  is  very 
faint  with  the  intensity  control  at  maximum. 
You  have  checked  the  schematic  and  de- 
cided to  measure  the  divider.  According  to 
the  manual  this  point  should  be  at  -560  vdc 
in  respect  to  the  chassis.  If  you  want  to 
impose  the  least  possible  load  on  the  circuit, 

do  you  use  the  1000  volt  range  on  your 
20,000  ohm  per  volt  VOM  or  on  your 
VTVM,  with  its  1 1  meg  input? 

If  you  said  the  VTVM  go  directly  to  jail, 
do  not  pass  go,  do  not  collect  $200,  The  cor- 
rect answer  is  the  VOM,  The  VOM  on  the 
1000  volt  rangex  20,000^2-20  megohms,  or 
nearly  double  the  input  resistance  of  the 
VTVM  and  for  this  reason  would  load  the 
circuit  only  H  as  much. 

.  „  .  BiU  Turner  WA0ABI 


NEW 


8TH  EDITION 

of  the  famous  E  &  E 


BIGGEST  SELLING  BOOK  FOR  THE 
AMATEUR  AND  ENGINEER 

Completely  revised  and  updated  by  William  I, 
Orr*  W6SAL  This  is  the  comprehensive  com- 
munications manual  which  is  the  industry 
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No,  65168,  New  18th  Ed.  RADIO  HANDBOOK. 
Special  price  until  Dee,  31,  1969,  onJy.. 

(After  Jan,  1.  i9?0,  regular  prict  wtll  be  $13.50) 

Order  from  your  electronic  parts  distributor 
or  bookstore,  or  send  coupon  below: 

r  -Howard  W,  Sams  &  Co.,  Inc.— 

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4300  W,  62nd  St.,  Indianapolis,  Ind.  46268 

D  Sendmethe  new  18th  Edition  RADIO  HANDBOOK 
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$ .,.,.  enclosed.  □  Check  Q  Money  Order. 


1 
I 


Name 

Address 

City 

state 

Zip 

I 


J 


OCTOBER   1969 


t9 


I 


Chuck  Hines  K6QKL 
86 IS  Idlewood  Drive  SW 
Tacoma,  WA  98498 


FET  Chirver 


The  Chirp er  is  an  automatically  keyed, 
crystal  controlled,  signal  source  which  may 
be  used  to  optimize  the  signal-to-noise  ratio 
of  a  receiving  converter*  Homebrew  or  com- 
mercial, converters  are  a  common  thing 
around  an  amateur  station.  And,  most  of  the 
VHF  Tribe  have  read  thru  a  jungle  of 
esoterica  dealing  with  low  noise  front  ends, 
the  velvet  beauty  of  FET's  on  Two,  noise 
generators  and  eternal  truth,  and  how  to 
copy  20  db  below  the  noise  by  the  selective 
use  of  Uquid  helium.  With  a  kind  of  re- 
lentless evolution  converters  have  been 
getting  better  and  better,  noise  figures  be- 
come lower,  and  the  prices  of  suitable  front 
end  devices  are  dropping  by  the  hour.  But 
when  it  comes  to  aligning  these  converters 
the  scene  is  one  of  wretchedness.  A  black  art 
at  best,  the  job  is  taken  up  with  an  enduring 
combination  of  blunt  instrument  and  myth. 
The  latter  have  a  certain  charm.  Are  you 
convinced  your  converter  is  in  top  notch 
condition  because  you  can  *'hear  noise" 
when  you  attach  the  antenna  —  or  better 
yet,  when  you  place  a  50  ohm  resistor  across 
the  input?  Try  putting  a  complete  short 
across  that  same  input.  Shorts  aren't  much 
good  as  noise  sources.  You'll  find  the  short 
gives  about  the  same  change  in  noise  level  as 
the  50  ohm  termination.  What  has  changed 
is  the  impedance  the  front  end  "sees".  The 
same  is  partially  true  of  the  noise  from  the 
antenna.  Neither  is  indicative  of  the 
performance  of  the  converter.  Peaking  the 
system  up  for  maximum  on  either  a  weak 
signal  or  on  noise  gets  you  nowhere.  The 
diode  noise  generator  which  every  VHF 
book  of  substance  describes  is  a  good  and 
useful  tool  when  used  properly.  The  assump- 
tion is  that  everyone  already  knows  full  well 
how  to  use  it  and  does  so.  Few  in  fact  do. 

Vm  sure  you've  read  of  it  before  in  many 
places,  but  a  little  redundancy  is  in  order. 
The  noise  with  which  you  are  concerned  is 
the  noise  generated  internally  by  the  first 
tube,  transistor,  or  other  active  device  the 
signal  encounters  upon  its  arrival  at  your 
converter.    By    fiddling    with    the    external 


reactances,  adjusting  the  voltage  and  current 
and  otherwise  manipulating  the  things 
soldered  to  the  device,  one  may  minimize 
the  internally  generated  noise.  At  the  same 
time  the  reason  the  front  end  exists  is  to 
ampUfy  the  signal.  One  usually  desires  as 
much  amplification  possible,  short  of  smoke 

and  osciUatiOn,  Minimum  noise  and  maxi- 
mum amplification  is  the  game.  Though  the 
two  are  not  quite  mutually  exclusive  a 
certain  amount  of  compromise  takes  place. 
Thus,  the  signal  to  noise  ratio.  When  aligning 
a  converter's  first  stage  every  adjustment 
effects  both  signal  and  noise.  Given  a  con- 
stant signal  source  coupled  into  the  con- 
verter thru  an  appropriate  impedance,  the 
job  is  finished  when  the  front  end  has  been 
adjusted  for  the  greatest  difference  between 
signal  and  noise  of  which  it  is  capable. 

The  Chirper  is  designed  to  help  you  do  all 
this  by  letting  you  see  what  effect  each 
adjustment  has  on  both  signal  and  noise.  The 
TIS34  oscillates  at  a  frequency  controlled  by 
the  crystal  With  the  constants  shown,  that 
can  be  anywhere  between  8.2  and  36  MHz. 
The  variable  capacitor  must  be  adjusted  for 
resonance.  It  isn't  particularily  critical  but 
its  setting  peaks  the  rf  output  at  either  the 
fundamental  or  some  harmonic.  For  6 
meters  an  8.35  MHz  crystal  is  used,  A  9,0 
MHz  rock  will  pin  the  meter  when  the 
Chirper  is  connected  into  a  2  meter  con- 
verter. The  Amidon^  toroid  is  wound  with 
No.  30  enameled,  40  turns  for  the  primary 
and  5   turns  for  the  secondary.  After  it  is 

1,  12033  Otsego  St.,  N.  Holiywood,  CA  91607 


20 


73  MAGAZINE 


NRCI's  compact  new  happening  puts  you  on 
AM  coverage  of  the  80  through  10  meter 
including  built-in  AC  power  supply  and  mon 
and  you'll  see  this  is  the  rig  to  stay  with! 

1000  Watts  PEP  on  SSB,  1000 
Watts  CW,  500  Watts  FSK,  500 
Watts  AM. 

All-solid-state  except  for  driver 
and  PA. 

Built-in  RF  speech  clipper. 


the  air  with  comphte  SSB,  CW,  and 
bands.  There's  a  lot  in  it  for  you, 
itor  speaker.  Check  these  features, 

Wide- range  fast  attack /slow  de- 
cay AGC, 

Receive   Vernier    with    separate 
on /off  control. 

Suggested    amateur    net    price, 
$995. 


For  complete  (and  impressive)  specifications  and  details,  write: 

NATIONAL  RADIO  COMPANY,  INC 

NnCI   37  Washington  St..  Melrose,  Mass.  02176 


®  1969,  National  Radio  Company,  Inc. 


Internatfonal  Marketing  through: 
Ad  Auriema,  Inc.,  85  Broad  St.,  New  York,  N.Y.  10004 


AMIDON 
T-50-10  CORE 


Fig.  1.  Schematic  of  the  FET  chirper. 

wound,  spread  the  turns  to  fill  the  toroid 
and  paint  it  with  Q  dope.  The  diode  and  5 
pF  coupling  capacitor  are  connected  with 
the  shortest  possible  leads,  the  diode  being 
grounded  at  the  rf  connector.  The  harmonic 
output  is  excellent  and  quite  useable  at  1200 


The  oscillator  is  turned  on  and  off  by  a 
multivibrator    combination    of   unijunction 
and  NPN  transistor  adapted  from  the  G.  E. 
Transistor  Manual    The  rate  at  which  the 
multivibrator  cycles  is   determined  by  the 
large  value  capacitor,  in  this  case  33  mF.  The 
polarity  of  the  capacitor  is  critical.  Observe 
it.  To  increase  the  cycHng  rate,  decrease  the 
capacitance;  and,  to  decrease  the  rate,  put  in 
a  larger  value.  Mine  cycles  a  little  under  once 
per  second.  A  value  somewhere  between  30 
and  40  mF  should  suit  your  needs.  You  are 
better  off  scrounging  some  odd  value  from  a 
defunct    computer   board    because    of   the 
tolerance  problem.  If  it  says  33.2  mF,  its 
probably  pretty  close  to  that  value.  Other- 
wise you're  dealing  with  tolerances  of  plus 
100%  and  minus  50%  or  something  equally 
grotesque.    The    50K    pot    determines    the 
portion    of    the    cycle    during    which    the 
oscillator  is  On  and  is  mislabeled  rate  on  the 
Chirper  shown.   The   HEP-310  is  generally 
available    and    inexpensive.    Other  un^junc- 
tions  were  not  tried.   On   the  other  hand 
almost  any  NPN  of  reasonable  quality  will 
work  in  place  of  the  2N7I8.  A  number  of 
2N388   and    2N3478's   were   tried   and   be- 
haved well.  It's  a  good  place  to  use  tho§e 
transistors  youVe  replaced  with  FET's.'Use 
something  with  a  Beta  of  50  or  better  for 
best  results.  The  5100  ohm  resistor  in  series 
with   the  pot   is  for  current  limiting.   It's 
deletion  will  increase  battery  drain  with  no 
incyease   in    Chirper   performance.    Normal 


current  from  the  9  volt  battery  is  around  5 
mA. 

Construction    is  non-critical  and   pretty 
much  a  matter  of  taste.  Mine  is  built  on  a 
piece    of   vector-board   and   mounted  in   a 
Suzurando^  box,  model  M-IN.  It  measures 
3^4  X  2  X  4"  and  there  is  still  room  inside 
for  additions.  It  sells  for  330  yen,  about  92c. 
A  slide  switch  is  used  to  turn  the  power  on 
and  off.  Paint  one  well  of  the  slide  switch 
with  red  paint  -  Tester's  Pla,  a  model  plastic 
paint,  is  good  -  and  the  switch  will  indicate 
its  position.  Red  for  On  and  black  for  Off. 
It  saves  batteries.  Check  your  work  and  the 
polarity  of  the  large  capacitor.  Re-check  the 
connections  to  all  the  semi-conductors.  With 
four  different  kinds  of  devices  things  can 
become  confused.  Set  the  pot  to  the  middle 
of  its  range.  Insert  a  crystal  in  the  socket. 
Connect  the  Chirper  to  your  converter,  turn 
the  switch  on  and  adjust  the  variable  capaci- 
tor for  the  highest  reading  on  your  S-meter. 
The  oscillator  will  turn  on  and  off.  Varying 
the  pot  will  extend  or  diminish  the  amount 
of  time  the  oscillator  is  on.  Whatever  you 
do,  don 't  connect  the  chirper  to  an  external 
antenna.  The  harmonic  content  is  high  and 
even  at  this  power  level  is  sufficient  to  cause 
severe    interference    to    television    receivers 
within  a  two  block  radius, 

I    VTVfm  \ 


CHtflPER 


C 


ifTtwATnn 


CONVERTER 


Fig,  2.  Test  set-up  for  converter  alignment. 

For  converter  ahgnment,  the  test  set-up  is 
illustrated  in  Fig.  2.  The  Chirper  is  fed  to  the 
converter     thru     an    attenuator     for    two 
reasons.    First,    the    power    output    of  the 
Chirper  is  too  high  on  six  and  two.  You 
don't  want  to  align  with  a  forty  over  nine 
signal.    Something    around    S-5    to    S-7    is 
desired.  Second,  the  attenuator  maintains  a 
50  ohm   termination  for  the  converter.   A 
converter  cannot  be  aligned  with  a  floating 
input  impedance.  Fixed  and  variable  attenu- 
ators of  excellent  quahty  are  available  thru 
surplus  and  homebrew  data  is  available.  See 
7S,  January  67,  p.  40  for  one  that  will  do 
the  job.    Turn    the   receiver  avc  off.   The 
read-out    options  are   diverse.   The   best   is 
pr<>bably   a  scope  connected   to  the  if.   A 
vtvm  can  be  used,  connected  to  the  audio 
output.  And,  the  S-meter  can  be  used  with 
the   avc   on  fast.    This   will  vary   with  the 

2.Suzurando,  1-10-11  Sotokanda  Cbiyodaku,  Tokyo 


22 


73  MAGAZINE 


1 


receiver  and  it*s  particular  time  constants. 
What  needs  to  be  avoided  is  avc  pumping 
that  interferes  with  your  readings. 

Turn  the  Chirper  on,  adjust  the  attenua- 
tor for  a  convenient  signal  level.  When  the 
oscillator  is  on,  you're  reading  signal  When 
the  oscillator  is  off,  you^re  reading  noise  (on 
the  scope,  vtvm,  S-meter,  etc.).  As  you  make 
adjustments  on  your  converter,  observe  the 
effect  on  both  signal  and  noise.  Adjust  for 
the  greatest  difference  between  the  two. 
Turn  the  Chirper  off  and  re-check  the 
converter  neutralization.  If  necessary,  re- 
neutralize  the  converter  and  go  thru  the 
whole  thing  again.  Talking  about  it  makes  it 
seem  somewhat  complex.  It  really  isn't  and 
the  whole  business  won't  take  long  once 
youVe  done  it.  It  will  become  quickly 
apparent  that  highest  signal  level  and  lowest 
noise  level  do  not  coincide.  You  can  vary  the 
bias^  voltage,  etc.,  and  observe  the  effects  of 
each  on  the  signaHo-noise  relationship.  You 
can^  in  short,  optimize  your  converter's 
performance, 

A  number  of  things  can  be  done  with  the 
Chirper,  There  is  room  in  the  box  to  build 
another  oscillator  section  connected  to  the 
transistor  coUector,  operating  in  parallel  and 
simultaneous  with  the  first  oscillator-  By 
appropriate  choice  of  crystal  and  attenua- 
tion, both  signals  can  be  introduced  into  the 
converter  in  order  to  adjust  the  mixer  for 
minimum  cross  modulation- 

Or,  instead  of  using  an  oscillator  at  all, 
you  can  use  the  switching  section  of  the 
Chirper  to  key  a  noise  generator  on  and  off. 
This  has  a  certain  attraction  where  an 
integrating  network  is  used  prior  to  a  vtvm. 
In  this  case  noise  is  used  as  a  signal. 

In    spite    of   it*s    name,    the    Chirper  is 

remarkably  stable.  Chirp  becomes  apparent 

from  two  meters  or  so,  but  is  no  problem. 

Build  one  and  take  the  myths  out  of  your 

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m 


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223  Pullman  Ave. 
Rochester  NY  14615 


on 


As  long  as  there  have  been  radio 
amateurs,  hams  have  been  interested  in  the 
telephone  system  and  sought  ways  to 
integrate  it  into  ham  communications.  The 
worth  of  this  idea  needs  no  explaining.  With 
their  great  tradition  of  pubhc  service  and 
emergency  work,  ham  operators  have  time 
and  again  proven  their  skill  and  efficiency  in 
time  of  need.  Nonetheless,  in  order  to  be  a 
truly  effective  service,  ham  radio  should  be 
ready,  whenever  necessary,  to  utilize  any 
and  all  media  for  communications.  In  spite 
of  the  fact  that  the  two  services  grew  up 
together,  comparatively  little  data  of  any 
value  is  available  for  our  use.  Therefore  the 
ham  is  often  inclined  to  experiment  on  his 
own.  This  clandestine  activity  can  have 
tragic  results  in  the  form  of  angry  telephone 
officials,  and,  in  some  cases,  can  produce 
real  damage  to  the  telephone  system,  to  say 
nothing  of  the  expensive  ham  equipment. 

In  all  fairness  to  the  telephone  people,  it 
should  be  pointed  out  that  a  service  so 
widespread  as  theirs  can  become  night- 
marishly  complex.  Take  the  telephone  found 
in  the  average  home.  It's  a  lot  more  intricate 
than  the  cheap  field  phones  they  used  to  sell 
in  the  Radio  Shack, 

The  diagram  is  the  result  of  the  dissection 
of  a  surplus  telephone,  rather  than  any 
revelation  by  Mr.  Bell.  With  the  receiver 
hung  up,  S4  and  S5  are  held  open*  A  strong 
ac  signal  can  pass  through  C2  and  ring  the 
bell  J  but  the  rest  of  the  instrument  is 
disconnected.  When  you  pick  up  the  phone, 
S4  and  S5  close.  As  you  start  to  dial,  SI 


opens  disconnecting  the  earphone,  and  S2 
closes.  As  the  dial  return s^  S3  opens  and 
closes  pulsing  the  hne.  You  can  follow  the 
circuit  from  the  red  lead  through  S2,  which 
remains  closed  until  the  dial  reaches  its  rest 
position,  then  through  the  pulser,  S3, 
through  S5  (closed  because  the  receiver  is 
up)  and  out  via  the  green  lead.  A  dc  voltage 
is  present  on  the  line,  and  the  closing  of  S3 
shorts  it  out,  producing  pulses  which  are 
sensed  by  the  stepping  relays  at  the  central 
office. 

After  you  have  finished  diaUng,  SI  and 
S3  are  closed,  and  S2  is  open.  The  dc  voltage 
now  reaches  the  mike  from  the  green  lead, 
through  S5  and  S3,  through  the  mike^  then 
into  the  auto  transformer,  L,  where  it  is 
stepped  up  and  sent  out  over  the  line.  The 


PHO 


yic, 


< 
S 


r      y^ 


^B2  nc 


Fig.  1,    Diagram  of  a  run-of-the-mill  Bell  tele 
phonQ, 


24 


73  MAGAZINE 


capacitor,   CI    blocks   dc    from   the   auto- 
transformer. 

The  dc  voltage  on  the  line  is  in  the  order 
of  48  volts  when  it  leaves  the  exchange,  but 
can  be  considerably  reduced  by  the  time  it 
reaches  the  subscriber.  Sufficient  tolerance  is 
built  into  the  system  to  aUow  a  wide 
variation.  The  signal  which  rings  the  bell  is  a 
20  hz.  The  voltage  of  the  ac  is  48  volts,  but 
since  it  is  superimposed  on  the  dc,  it  can 
sum  up  to  a  total  of  96  v.  The  dial  tone 
varies  from  exchange  to  exchange.  Anything 
that  will  make  a  sound  wiQ  do. 

A  line  from  the  exchange  to  the  sub- 
scriber is  called  a  loop.  The  overall  im- 
pedance can  range  from  900  ohms  to  about 
1,5  k,5  although  they  like  to  shoot  for  a 
happy  medium  of  1.2  k.  Since  the  sub- 
scriber's telephone  is  midway  around  the 
loop,  it  looks  into  an  impedance  of  around 
600  ohms,  and  this  value  is  the  standard 
value  used  by  radio  stations  in  a  remote 
broadcast  loop.  The  frequency  bandpass  for 
conversational  subscribers  is  300  to  3k hz. 
This  has  proven  most  effective  for  trans- 
mission of  speech  with  the  highest  intelligi- 
bility: Broadcast  loops  come  in  several 
classes-  One  has  a  passband  essentially  the 
same  as  a  standard  telephone  loop.  This  class 
is  used  most  often  for  sports  and  newscasts- 
The  class  of  loop  used  for  disc  Jocky  type 
programs,  where  some  transmission  of  music 
is  required,  passes  up  to  8  khz,,  and  finally, 
FM  stations  occasionally  use  the  most  ex- 
pensive class  with  a  full  audio  passband. 
(With  very  few  exceptions,  AM  broadcast 
stations  have  an  audio  bandwidth  limiting  at 
6  khz.) 

Audio  levels  for  the  telephone  system  are 
centered  around  a  reference  (O  db)  of  1 
milliwatt  across  a  600  ohm  load.  Broadcast 
loops  generally  hold  their  audio  levels  at  0  to 
+6  db.  Home  subscribers  have  no  engineer  to 
watch  a  level  meter,  and  so  it  is  difficult  to 
pin  down  the  audio  level.  Bell  system 
engineers  have  no  way  of  knowing  whether 
the  user  will  be  a  love-sick  bobby-soxer  or  an 
eight-year-old  telling  grandpa  about  the  fish 
he  just  caught.  These  represent  two  extremes 
for  audio  level.  For  design  purposes,  they  try 
to  consider  the  average  of  all  voltage  levels 
over  a  three-second  period  at  -12  db.  Using 
this  figure  as  a  design  center,  they  are  at 
least  able  to  minimize  crosstalk  between 
lines. 

When  the  receiver  is  lifted,  and  switches 
S4  and  S5  close,  a  dc  path  is  closed  for  the 
48  volts  on  the  line.  The  resultant  current 


closes  a  relay  in  the  central  exchange  which 
connects  you  into  an  available  line  to  dial, 
and  isolates  your  phone  from  incoming  calls. 
As  you  dial,  the  pulser,  S3,  produces  a  series 
of  brief  shorts,  so  far  as  your  telephone  is 
concerned.  At  the  exchange,  however,  these 
"shorts"  are  seen  as  a  series  of  current 
pulses.  These  pulses  go  into  a  device  similar 
to  a  stepping  relay,  which  counts  the  pulses 
and  connects  your  phone  to  a  set  of  contacts 
determined  by  the  first  digit  you  dialed. 
Each  set  of  contacts  is  connected  to  a 
second  stepping  relay.  The  relay  on  the  set 
of  contacts  corresponding  to  your  first  digit 
is  pulsed  when  you  dial  the  second  digit. 
This  connects  you  to  a  third  stepping  relay, 
and  so  on  until  you  have  dialed  the  full 
number.  The  final  position  of  the  last  relay 
is  connected  to  the  telephone  you  are 
calling.  The  presence  of  your  signal  trying  to 
reach  this  number  closes  another  relay  which 
sets  the  ringing  mechanism  into  motion. 

The  ringing  mechanism  sends  a  48  volt  ac 
pulse  into  the  line  you  are  calling.  This  pulse 
passes  through  the  blocking  capacitor  and 
rings  the  bell.  When  that  line  is  picked  up,  its 
current  censor  closes  making  the  final 
connection.  The  ring  pulse,  by  the  way^  is 
one  of  two  possible  signals,  depending  on 
the  service  you  have.  Both  are  based  on  a 
5 -second  cycle,  A  **long"  ring  is  on  for  one 
third  of  the  time  and  off  two  thirds.  Some 
phones  ring  in  a  sequence  of  two  short  rings, 
each  one  sixth  of  the  time  with  one  sixth 
interval  between  them,  and  then  pause  for 
one  half  of  the  time. 


1209 


1336 


1477 


1633 


S9T 


O — 0 — 0 — O 


770 


es2 


94» 


Fig.  2.    Touch-tone  switching  matrix. 

The  touch-tone  system,  now  available  in 
some  localities,  sends  a  combination  of  two 
audio  tones  down  the  line  which  trip  a 
frequency  sensitive  relay.  From  there  the 
sequence  is  similar  to  the  dial  system  except 
that    frequency    sensitive    relays    are    used 


1 


OCTOBER    1969 


25 


instead  of  the  stepping  relays.  The  combina- 
tions are  given  in  the  matrix  shown  here. 
The  tones  for  any  given  digit  are  determined 
by  the  intersection  of  the  tone-lines  at  which 
the  button  is  located.  For  example,  the  digit, 
4,  would  send  out  a  combination  of  770  hz^ 
and  1209  hz.  The  two  figures  in  the  bottom 
row,  #  and  *  are  only  available  on  certain 

military  and  industrial  phones.  The  941  hz 
signal  only  appears  in  a  standard  phone 
when  the  zero  button  is  pressed.  The  fourth 
vertical  row  (1633  hz)  is  not  used  at  present, 
except  in  certain  data-transraission  systems. 
For  the  most  part,  it  is  reserved  for  further 
expansion. 

The  descriptions  given  so  far  are  a  very 
simplified  version  of  what  goes  on  when  you 
make  a  phone  call.  Multiply  this  by  a 
theoretical  ten  million  possible  number 
combinations  and  you  can  get  a  slight  idea 
of  the  nightmarish  complexity  of  the 
system.  One  small  goof  by  some  character 
who  doesn*t  quite  know  what  he  is  doing, 
reflecting  back  through  the  central  ex- 
change, can  upset  the  whole  applecart-  The 
telephone  system,  being  an  emergency 
service,  is  therefore  protected  by  federal  and 
state  laws  against  any  tampering  that  might 
disrupt  the  service  or  invade  anybody's 
privacy.  As  one  telephone  engineer  explained 
to  me,  **It*s  not  that  we're  trying  to 
monopolize  the  equipment,  but  unless  we 
know  what  is  hung  on  that  line,  we  can't  do 
our  job.  Also,  you're  paying  for  the  service, 
not  the  lines.  If  you  put  on  an  extension 
phone  of  your  own,  you're  taking  service 
that  you're  not  paying  for/* 

Over  the  years,  Amateur  Radio  has 
proven  its  worth  time  and  again  in  emer- 
gencies. When  disaster  strikes,  it  is  good  that 
all  services  can  work  together  and  combine 
all  available  facilities  for  the  public  good. 
Now  the  telephone  company  cannot  and 

does  not  object  to  the  infinitesimal  amount 
of  competition   offered   by   hams   chatting 

long  distance  over  the  air.  But  when  we  use 
their  own  facilities  to  phone-patch  a  pleasure 
call  in  competition  with  them,  you've  got  to 
admit  that's  getting  a  bit  dirty.  While  the 
telephone  company  won't  go  broke  from  the 
loss  of  an  occasional  service  charge,  the 
reputation  of  Amateur  Radio  is  far  too 
valuable  to  attow  it  to  be  cheapened  by  so 
small  a  thing  as  that.  What  1  have  told  about 
the  telephone  system  so  far,  as  well  as  what  I 
am  about  to  tell,  is  not  by  any  means  being 
revealed  so  that  my  brother  hams  can 
outsmart  Mr.  Bell,  but  rather,  if  the  need 
should  ever  arise ^  that  they  might  have* the 


know-how  necessary  to  make  use  of  every 
available  facihty  for  the  good  of  their 
fellow-men.  In  such  a  case  as  that,  even  the 
strictest  of  the  telephone  people  would  very 
probably  go  along  with  you-  And  so  I  clear 
my  conscience  with  the  reminder  that  you 
receive  with  this  knowledge  a  responsibility 
to  use  it  only  to  the  greater  credit  of  the 
fraternity.  One  clown  can  ruin  things  for  all 
of  us. 

When  it  comes  to  coupling  into  a  tele- 
phone line  with  equipment  of  other  than 
Bell  System  design,  we  should  look  first  at 
the  broadcast  stations.  They  do  this  sort  of 
thing  on  a  far  larger  scale  than  any  other 
telephone  company  customer*  In  the  broad- 
cast industry  the  most  common  method  is 
transformer  coupling.  Broadcast  loops  are 
generally  treated  as  if  they  were  600  ohm 
balanced  Unes.  Therefore,  any  600  ohm 
transformer  winding  should  offer  a  decent 
match.  It  is  worth  noting  that  the  telephone 
people  sometimes  clear  their  lines  with  a 
high-power  surge  at  around  500  volts  dc-  A 
blocking  capacitor  of  sufficient  capacity 
with  a  good  high  voltage  rating  can  save  you 
a  lot  of  grief.  Remember  also  that  the  600 
ohm  winding  only  looks  like  600  ohms  if  the 
other  winding  is  properly  matched.  If  the 
transformer  has,  for  instance^  a  10  K 
primary  and  a  600  ohm  secondary,  it  must 
have  a  10  K  load  across  the  primary.  Also, 
some  means  should  be  provided  to  insure 
that  the  audio  level  does  not  exceed  about  0 
db,  even  if  it  means  buying  a  meter.  For 
those  who  want  to  stay  on  the  good  side  of 
Mr,  Bell,  the  telephone  company  makes 
available  in  many  places  a  coupling  trans- 
former together  with  a  telephone  fitted  to 
automatically  remove  it  from  the  line  when 
the  receiver  is  down.  After  a  $5  installation 
charge,  it  only  adds  50c  a  month  to  your 
bill. 

If  you  intend  to  record  off  the  phone, 
remember  that  the  law  requires  that  a 
'*beep^'  be  sounded  on  the  line,  or  that  the 
other  party  know  right  from  the  start  that  a 
record  is  being  made. 

There  are  a  number  of  low-priced 
induction  pickups  on  the  market  which 
work  by  detecting  the  magnetic  field  of  the 
auto  transformer  or  of  the  earphone.  These 
not  only  work,  but  they  will  also  feed  a 
signal  into  the  line  if  the  level  is  high 
enough.  However,  unless  the  other  party  is 
aware  of  it  from  the  begiiming,  it  may  prove 
to  be  a  violation  of  the  federal  wiretap 
laws,  , 

The    diagram    shows    aU   the   necessary 


26 


73  MAGAZINE 


LET  DOW-KEY  HELP  SOLVE  YOUR  ANTENNA 

SWITCHING  PROBLEMS . . . 


SPOT 

REftlOTE  115V  ac 

60262842 


SP6T 

MANUAL  VIE1>^  L'  Wl^^f^  ^P6r 

78-0604  ^r    mmg^'^r^^  remote  usv  le 

71*260401 

SERIES  78  The  series  78  coaxial  switches  are  manually  operated  with  true  coaxial  switching  members  (not  wafer 
switches).  They  are  offered  in  2,  3,  4  &  6  position  (illustrated)  types,  plus  a  transfer  or  crossover  and  DPDT.  The 
useful  frequency  range  is  0-1  Ghz  except  500  Mhz  using  UHF  connectors.  The  unused  positions  are  open  circuited 
or  non-shorting.  Aiso  available  with  other  type  connectors  such  as  N,  BNC,  TNC  or  C. 

SERIES  60  The  series  60  are  remote  operated,  of  rugged  construction  and  designed  for  low-level  to  1  KW  use. 
The  unit  illustrated  is  equipped  with  a  special  high  isolation  connector  ("G"  type)  at  the  normally  closed  or  re- 
ceive position.  This  "G*'  connector  increases  the  isolation  to  greater  than  -lOOdb  at  frequencies  up  to  500  Mhz, 
although  it  reduces  the  power  rating  through  this  connector  to  20  watts.  This  is  also  available  with  other  type  con- 
nectors such  as  BNC,  N,  TNC„  C  or  solder  terminals. 

SERIES  71  High  power  6  position  switches  commonly  used  for  switching  antennas,  transmitters  or  receivers 
at  frequencies  up  to  500  Mhz.  The  unit  is  weatherproof  and  can  be  mast  mounted.  The  illustrated  unit  has  the 
unused  input  shorted  to  ground.  It  is  atso  available  with  a  wide  range  of  connectors,  different  coil  voltages  and 
non-shorting  contacts  or  resistor  terminations.  Each  of  the  six  inputs  has  its  own  actuating  coil  for  alternate  or 
simultaneous  switching. 


■■*5v 


-  IKS^ 


ORDERING  INFORMATION: 

Contact  your  local  electronics  distributor  or  Dow-Key 
COMPANY  *^^^*   /epresentaiive,   or   writ©   direct   to    the    factory. 


2260    INDUSTRIAL  LANE    »    BROOMFTELD.   COLORADO    80020 
TELEPHONE    AREA    CODE    303/46^-7303         •         F.  O.   BOX  343 


tOU€ 
SOOVt 


Fig.   3,      Isolating  circuit  for  coupling  to 
phone  line, 

elements  for  coupling  into  or  out  of  a 
telephone  line.  The  three  resistors  may  be 
entirely  unnecessary  if  the  primary  winding 
of  the  transformer  matches  exactly  the 
circuit  feeding  it.  Using  realistic  values, 
however,  it's  perfectly  possible  to  have  a  20 
K  transformer  and  a  1  meg  recorder  or 
modulator  input.  If  such  were  the  case,  R2 
would  have  to  equal  the  transformer  im- 
pedance, (in  this  instance,  20K)  Rl  in  series 
with  R2  should  equal  the  apparatus  im- 
pedance (1  meg.)  The  values  are  different 
enough  that  Rl  could  be  1  meg,  and  the 
series  combination  of  Rl  and  R2  would  not 
make  that  much  difference.  With  this 
arrangement,  R3  could  be  left  out.  This 
could  take  audio  off  the  line  quite  effective- 
ly, but  it  would  have  a  50: 1  attenuation  if 
you  tried  to  feed  voltage  in.  Much  better  to 
properly  select  your  transformer  in  the  first 


place.  Taking  another  case,  suppose  you 
were  using  the  same  transformer  as  before, 
but  feeding  it  from  a  10  K  source.  R2  would 
stOl  match  the  transformer,  R3  would  match 
the  source  (10  K),  Rl  would,  have  to  be 
about  10  times  the  larger  of  the  other  two 
(in  the  case,  200  K).  If  the  apparatus  had  an 
impedance  equal  to  the  primary  impedance 
of  the  transformer,  you  could  then  leave  out 
all  three  resistors  and  there  would  be  no 

attenuation.  The  meter,  M 1  is  a  standard  VU 
or  decibel  meter  to  ensure  that  the  lever 
going  out  onto  the  hne  were  the  same  as  that 
coming  in  (no  more  than  0  db).  The 
capacitor  serves  to  block  against  any  high- 
power  dc  surge,  and  is  picked  so  that  the  Xc 
is  about  1/10  that  of  the  line,  I  have  given 
enough  information  for  the  ham  who  is 
reasonably  proficient  in  the  art  to  quickly 
calculate  the  proper  values  to  meet  his 
needs.  In  the  interests  of  Amateur  Radio, 
and  also  in  the  interests  of  the  reader,  if  you 
cannot  figure  out  the  proper  values  with  the 
information  given  here,  I'd  say  don't  mess 
with  the  line.  Unless  you  really  know  your 
stuff,  it's  better  for  you  to  buy  a  pickup  coil 
or  pay  the  extra  few  bucks  to  the  phone 
company  for  one  of  their  couplers.  .  W2FEZ 


OCTOBER    1969 


27 


Dave  Mann,  K2AGZ 
One  Daniel  Lane 

Kinnelon,  New  Jersey  07405 


Leaky   Lines 


I've  been  lambasting  the  editorialist  of  QST  for 

quite  a  while,  on  the  basis  of  his  ill-conceived  piece 

last  February  concerning  freedom  of  speech.  After 

a   couple    of  recent  experiences,  1   have   revised 

slightly  my  stated  views  on  this  matter,  and  would 

like  to  outline  my  current  ideas  on  the  subject 
You  will  recall  that  I  opposed  the  notion  that 

freedom  of  expression  should  be  censored  in  any 

way*  I  said  then  that  mature  and  intelligent  people 

are  capable  of  discussing  anything  under  the  sun 

without  becoming  emotional  or  insulting-  1  still 

feel  this  to  be  valid.  Unfortunately,  1  did  not  take 

into  account  the  fact  that  there  are  some  who  are 

not  all  that  intelligent.  1  neglected  to  remember 

that  there  are  people  who  will  go  out  of  their  way, 

and  seek  deliberately  to  hurt,  out  of  intolerance, 

bigotry,  envy,  or  some  fancied  grievance* 

There  are  many  malcontents  in  this  world,  and 
we  have  our  fair  share  of  them  in  Amateur  Radio, 
There  are  bullies,  misfits,  paranoids,  and  a  whole 
range  of  peculiar  types  who  are  not  prepared  to 
maintain  that  degree  of  dispassionate  detachment 
which  would  permit  discussion  minus  any  violent 
verbal  abuse.  The  very  existence  of  this  group  casts 
some  skepticism  into  my  mind  now,  about  the 
wisdom  of  my  words;  I  have  misgivings. 

It  isn^t  proper,  after  all,  to  steer  clear  of  foul 
language,  if  I'm  going  to  turn  right  around  and 
backbite  some  other  ham.  I  may  never  utter  a 
sacrilege,  yet  I  may  get  away  with  slander,  libel  or  1 
may  bear  false  witness.  Though  1  may  avoid  highly 
charged  questions  and  pohtical  controversy,  I  may 
indulge  in  hypocrisy  of  the  vilest  kind. 

There  seems  to  be  some  idea  that  if  a  guy  waves 
Old  Glory  and  says  he  believes  in  the  sanctity  of 
motherhood  and  the  home,  he  is  then  perfectly 
free  to  go  on  the  air  and  express  all  kinds  of 
poison  J  without  fear  of  retribution-  He  can  say 
anything,  (so  long  as  he  doesn't  cuss,)  about 
another  race,  creed  or  color.  He  has  only  to  avoid 
foul  language,  treason  and  sedition,  heresy  or 
irreverence,  and  he  is  witiiin  bounds. 

I  don't  mean  to  suggest  that  we  should  not 
express  dislike  or  disapproval.  But,  if  you  feel  that 
someone  is  an  unmitigated  scoundrel  or  a  plain 
louse,  don't  tell  some  third  party  about  it  on  the 
air.  it  sounds  horrible.  Put  it  in  a  letter  to  him,  or 
call  him  on  the  phone,  and  tell  him.  Or  better  yet, 
try  to  ignore  the  whole  thing,  and  save  yourself  an 
ulcer.  We'll  all  be  better  off 

Apropos  this  question  of  contempt  for  others,  I 
wonder  if  youVe  seen  some  "letters  to  the  editor*' 


from  some  of  the  younger  hams.  Fm  getting  a  bit 
fed  up  with  characters  who  automatically  classify 
everyone  over  thirty  an  old  fogey-  They  tend  to 
put  their  age  alongside  their  signature,  as  if  to 
proclaim,  "Look  what  a  bright  and  precocious 
child  1  am*  " 

They  say  we  aren't  keeping  up  with  electronics, 
and  call  us  a  flock  of  doddering  morons.  What  a 
crock  of  sophomoric  sassafras!  There  are  all  sorts 
of  persuasions  in  ham  radio*  But  1  warrant  that  the 
very  first  thing  that  attracted  almost  all  of  them» 
like  almost  all  of  us*  was  the  ability  to  communis 
cate;  that's  the  name  of  the  game.  Theory,  design, 
research,  construction  and  other  technical  facets 
almost  invariably  are  a  later  development- 
Why  does  a  teen-age  kid  presume  to  tell  his 
elders  that  they  have  no  right  to  indulge  their  own 
particular  desires  and  aspirations?  Are  only  the 
young  entitled  to  **do  their  own  thing?"  How  do 
some  people  arrive  at  the  startUng  conclusion  that 
anyone  who  does  not  share  their  standards  is 
somehow  unworthy?  Where  is  tlie  justification  for 

this  canard? 

This  hobby  is  all  things  to  all  hams,  and  if  some 
of  these  child  prodigies  don't  like  it,  perhaps  they 
should  forsake  ham  radio  and  cultivate  astro-phy- 
sics, brain  surgery  or  some  other  field  wherein  they 
may  breathe  the  highly  rarified  air  of  genius* 

I  resent  any  implication  that  everybody  who 
has  achieved  adulthood  is  a  doddering,  senile  cretin 
who  once  passed  a  test,  and  has  been  stagnating 
and  vegetating  ever  since.  Perhaps  we  have  lost 
some  of  our  bounce,  to  be  sure;  that's  Ufe.  But 
there  is  one  thing  we  like  to  think:  we  try  to  get 
along.  We  try  not  to  be  rude  and  discourteous  to 
others,  most  of  us.  And,  with  few  exceptions,  we 
do  not  treat  our  ham  colleagues  with  contempt  and 
disdain. 

I*d  love  to  be  around  to  hear  what  some  of 

these   'Vo^'^g  Turks'*  wUl  say,  some  fifteen  or 

twenty  years  hence,  when  some  college  punk,  still 

wet  behind  the  ears,  calls  them  dead  wood,  and 

says  they  ought  to  '^shape  up  or  ship  out." 

*  * 

First  **beisbol.'*  Then  motion  pictures  and  TV. 
Then  the  motorcar  and  airplane.  Then  moveable 
type,  penicillin,  radio  and  the  carburetor.  Oh  yes, 
pity  poor  Robert  Fulton  and  John  Fitch;  The 
Russians  also  invented  the  steamboat;  or  didn't 
you  know  that?  WImt  wiU  they  claim  next?  This 
reminds  me  of  the  old  Gershwin  song  which  went 
something  like,  but  not  precisely  like  this: 


28 


73  MAGAZINE 


They  all  laughed  at  Ivan  Tomashevski 

When  he  said  the  world  was  round, 

They  all  laughed  when  Popovich  recorded  sound, 

They  all  laughed  at  Vronski  and  Polonski 

When  they  said  that  man  could  fly, 

They  told  KazuUski  wireless  was  the  bull-ski 

That^s  the  same  old  cry„...etc, 

I'd  like  to  say  a  few  kind  words  about  SWL's. 
Not  so  much  extravagant  praise,  but  merely  some 
recognition  for  the  impulse  behind  the  cards  we 
sometimes  get  via  the  bureaus,  FVe  noticed  that  in 
addition  to  the  infoimation  they  convey,  some- 
times surprisingly  comprehansjve  with  respect  to 
conditions,  propagation,  and  so  forth,  these  people 
often  display  marked  ability  to  copy  code.  Some- 
how it  makes  all  the  little  carping  complaints  of 
the  anti-CW  proponents  seem  a  bit  unworthy.  The 
hams  who  propose  dispensing  with  the  code  as  a 
tequisite  for  a  license  should  devote  some  thought 
to  this.  The  SWL  wants  to  accumulate  QSL  cards 
from  hams.  He  therefore  sets  about  learning  how 
to  copy  CW.  There  is  no  requirement  that  he  do 
this.  The  achievement  is  its  own  reward.  He  has  a 
goalj  and  this  provides  him  with  the  necessiiry 
incentive.  How  then,  can  hams  indulge  themselves 
and  abandon  themselves  to  inertia  and  indolence, 
bemoaning  their  misfortune  at  having  to  meet  code 
^standards,  at  the  same  time  knowing  that  non-hams 
are  beating  them  at  their  own  game? 

I  hope  the  time  will  never  come  when  CW  is 
done  away  with*  Not  only  is  it  an  efficient  mode  of 
communication,  but  a  time-hallowed  and  tradit- 
ional part  of  our  historical  development*  Many  a 
golden  chapter  in  the  shining  ciironicle  of  Amateur 
Radio  would  never  have  been  written  but  for  this, 
our  first  and  most  venerable  method  of  transmit- 
ting radio  signals. 

*  * 

Remember  how  Charlie  CorreU  used  to  answer 
the  phone?  "Hello.  Dis  is  de  Fresh  Air  Taxicab 
Company.  Andrew  H,  Brown,  president,  speakin\" 
Then  came  the  sultry  voice  of  the  temptress, 
Madame  Queen.  "Hello,  Andy,"  Andy^s  tone  of 
voice  would  change  completely.  "Heeeee-lUoooo," 
he  would  drooL 

I'm  always  reminded  of  this  Amos  *n  Andy  bit, 
whenever  I  hear  the  following  phenomenon. 

A  flock  of  guys  are  on  the  air,  yapping  about 
this  and  that;  everything  in  general,  and  nothing  in 
particular.  Lots  of  kidding;  references  to  graying 
hair  or  baldness,  false  teeth,  and  bulging  waistlines, 
There^s  talk  about  grandchildren,  mobile  homes  in 
Florida,  and  moaning  over  little  aches  and  pains, 
bursitis  and  lumbago.  In  short,  from  all  indications 
these  gents  are  certainly  well  within  the  category 
of  middle  age,  and  perhaps  just  a  teensy-weensy  bit 
older* 

All  of  a  sudden  a  female  voice  is  heard,  'way  off 
in  the  distance,  just  about  a  smidgeon  above  the 
noise  leveL  Immediately  these  elderly  parties  are 
galvanized  into  a  strange  and  wonderful  meta- 
morphosis. In  one  fell  swoop  they  not  only 
develop  super-acute  hearing,  but  they  seem  to  shed 
the  accumulated  years  as  a  snake  molts  his  skin* 
They  revert  to  virile  rooster-hood  in  an  instant,  and 


they  become  a  gaggle  of  contending  tomcats, 
serenading  and  caterw^auling  to  some  feline  para- 
mour from  the  backyard  fence.  They  fall  all  over 
themselves  in  a  spirited  competition  for  the  lady*s 
attention.  From  the  sound  of  the  response  to  this 
tomatoe,  you  would  think  she  was  Raquel  Welch, 
Brigitte  Bardot  and  Sophia  Loren,  all  rolled  into 
one. 

Next  time  you  hear  a  YL  breaker^  pay  particu- 
lar attention  to  the  atavism  of  all  the  old  gaffers, 
and  see  if  you  don't  get  a  great  kick  out  of  it.  It's 
more  fun  than  monkey  gland  extract,  or  a  hor- 
mone injection,  and  who  knows?  It  might  just  be 
the  answer  to  the  growing  problem  of  geriatrics, 
There*s  nothing  like  a  little  old  fashioned  S  -  X  to 
stimulate  some  life  in  the  old  bones,  right? 

FAMILIAR  SOUNDS  DEPARTMENT 

"Hello,  CQ,  CQ,  CQ,  from  K2AGZ.  Kilo  two 

Alpha  Golf  Zulu  calling  CQ  and  standing  by." 

"K2AGZ.  K2.,.  „.  Z-  This  is  K Baker, 

wheeeeeeeeeeeeeeeeee."*'QRZ,  QRZ,  QRZ,  The 
station  calling  K2AGZ,  please  try  again.  QRM  took 
you  out.  This  is  K2AGZ  standing  by  for  you." 

'*K2AG*-...„this  is  KR7  Whhheeeeeeeeee, 

Hello  test,  one  two  three  four four  three  two 

one,  Whhhhheeeeeeee  squawk,  splatter,  squeak, 
crunch,  bang,  clang,  crash,  @t $%!&*()  testing, 
testing,  heeeeelllllllllloooooooooo  test," 

'^KR7  question  mark.  KR7  question  mark,  this 
is  Kilo  two  America  Germany  Zanzibar.  I'm  not 
quite  getting  your  caU,  old  man,  There*s  heavy 
QRM,  would  you  try  it  one  more  time  please? 
Over/' 

'*Heeeeeeelllllllllloooooooooo,  test* 
BBBBbbbbbZZZzzz,  RRRRrrrrRRRRRrrrrr.  Burp, 
wah-wah-wah,  tweet  tweet  tweet  tweet.  Whistle, 
tweed le-dee-dee.  Hallllooooo,  test  is  anybody 
using  this  frequency?" 

"Nobody  is  using  it.  Go  ahead,  old  man.  You're 
a  real  nice  fellow.  K2AGZ  clear  and  QRT."  *  *  * 

In  keeping  with  my  generally  iconoclastic 
attitudes,  I'd  like  to  give  the  "back  o'  me  hand"  to 
all  these  self-appointed  watchdogs  who  seem  to 
have  proliferated  recently  on  the  bands.  These 
screwballs*  of  course,  did  not  just  appear  out  of 
nowhere.  They  were  spawned,  in  my  view,  by  a 
recent  editorial  in  a  certain  magazine  which  saw  fit 
to  open  a  whole  can  of  beans  about  self-policing 
ourselves. 

Now,  there's  nothing  new  about  this.  Indeed, 
we  have  been  discussing  it  for  years.  In  fact^  it  is 
the  number  one  subject  of  the  speech  made  by  the 
Director  of  any  given  section,  at  the  annual  roast 
beef  dinner  of  tlie  Radio  Club,  But  this  time  it  was 
a  bit  different.  For  the  very  first  time,  someone 
came  out  in  print,  favoring  the  vitiation  of  one  of 
our  basic  Constitutional  privileges.  Freedom  of 
Speech.  But  Freedom  of  Speech  is  like  pregnancy 
or  death.  There *s  no  such  thing  as  a  little  bit  of  it. 
You  either  have  it  or  you  haven't! 

A  typewriter  is  Like  a  gun*  It  will  shoot 
anything  you  point  it  at.  The  man  behind  it  must 
exercise    good    judgment    at    all    times.    In    this 


I 


OCTOBER    1969 


29 


particular  case  the  man  behind  the  typewriter* 
obsessed  with  his  own  brilliance  and  wit,  having  to 
come  up  with  a  column  about  something  or  other* 
allowed  himself  to  make  an  error  of  judgment  .  He 
exhumed  this  moldy  fig  from  his  mildewing  trunk 
of  ideas,  never  reckoning  that  it  might  raise  a 
stench.  And  he  underestimated  the  common  sense 
of  the  readership! 

For  years  and  years  hardly  anyone  ever  took 
issue  with  the  pronunciamentos  which  came  down 
from  New  Mount  Sinai,  Connecticut  0611 L  Sacred 
cows,  like  other  ruminants,  become  so  absorbed  in 
the  chewing  of  their  cuds  that  they  develop  total 
obliviousness  to  their  surroundings;  a  sort  of 
self-mesmerism.  But  in  today's  world  things  are 
different.  There  are  no  longer  any  sacred  cows.  Or^ 
if  there  are,  they  simply  are  not  venerated  any 
more.  Poor  old  Hirohito  celebrated  his  birthday 
the  other  day,  and  it  rated  three  lines  on  page  27 
of  the  Paterson  Evening  News,  'When  Mr.  H,  H, 
Humphrey  crossed  the  street  in  St.  Paul,  a  cab 
driver  honked  his  horn  and  snarled  at  him,  and  two 
elderly  Republican  ladies  made  a  rude  gesture.  Sic 
transit  gloria  mundi! 

The  Editor  never  considered  that  this  piece 
would  provoke  a  deluge  of  protest  Who  woiilda 
thunk  it?  Wonder  of  wonders?  from  the  Sanctum 
Sanctorum  an  encyclical  had  been  pronounced,  yet 
it  was  not  accepted  unquestioningly  as  dogma.  This 
was  decidedly  not  the  reaction  he  had  anticipated. 

So in   the   next  issue  but  one,  along  with 

some  of  the  letters  of  objection,  the  Editor  wrote 
some  minor  retractions  and  statements  of  clarifica- 
tion,   which    sounded,    for    all    the   world,    like 

# 

backtracking.  He  had  to,  for  clearly,  the  natives 
were  restless.  To  the  everlasting  credit  of  amateur 
radio,  people  who  rarely  expressed  any  opinions  at 
alL  wrote  articulate,  intelligent,  and  even  brilliant 
denunciations  of  this  attempt  to  stifle  free  speech 
on  the  bands. 

Of  course,  there  were  some  who  agreed  with 
the  editorial.  I  have  heard  a  few  of  them^  anony* 
mously  playing  "vigilante"  on  the  air,  taking  issue 
with  those  with  whom  they  disagree.  Mostly  they 
concern  themselves  with  an  occasional  hell  or 
damn.  One  of  these  persons  is  a  confirmed  addict 
to  the  use  of '^By  Golly"  and  ''Jiminy  Cricket". 

Consulting  my  Partridge *s  Dictionary  of  Slang,  I 
came  up  with  the  following.  By  Gosh,  By  Golly 
and  By  Gum  are  expletive  substitutes  for  the  Name 
of  the  Deity.  Strange  to  say,  the  mild  expressions. 
Goodness  Gracious  and  Doggone  It  are  similarly 
derived*  Since  one  of  the  Ten  Commandments 
expressly  forbids  taking  the  Name  of  the  Lord  in 
vain^  somebody  devised  this  method  of  cussing 
without  actually  being  profane.  Semantically 
speaking,  however,  the  changed  words  do  not 
change  the  substance  or  context;  it's  still  swearing, 

Jiminy  Cricket,  Jumpin'  Catfish^  Gee  Whiz, 
Criminy  and  Cripes,  are  all  derived  from  the  Name 
of  the  Saviour,  and  their  use  is  every  bit  as 
objectionable  as  would  be  the  use  of  His  Name,  as 
innocently  as  they  sound! 

Shucks,  Pshaw,  Shoot  and  others  beginning 
with  the  consonantal  diphthong  "sh"  are  all  meant 


to  take  the  place  of  that  nasty  pejorative  which 
refers  to  a  certain  biological  function,  the  less  said 
about  which,  the  better.  In  this  group  is  included 
the  non  sequitur,  horsefeathers. 

Fudge  and  Phooey  I  leave  to  your  imagination; 
this  is  a  family  type  publication! 

I  hesitate  to  speculate  upon  the  derivation  of 
things  like  TU  be  hornswoggled,  or  111  be  jiggered. 
But  drat  it,  darn  it,  what  the  heck,  and  son  of  a 
gun  are  perfectly  obvious  to  anyone  with  half  an 
ear  for  sounds.  I  did  not  investigate  either,  into 
nifty,  to  get  one's  wind  up,  or  the  often  used 
bodacious. 

If  you  are  interested  in  just  how  hairy  tliis 
question  of  linguistics  can  get,  just  try  using  the 
terms,  slowpoke  or  bugger,  wliile  talking  to  a 
Britisher.  You're  likely  to  get  your  head  handed  to 
you. 

Well,  what  Pve  been  driving  at  is  this.  I  would 
far  rather  hear  someone  say  an  occasional  hell  or 
damn  than  some  of  those  overdone  cliches  which 
are  accepted  as  innocent.  There  is  no  valid  reason 
for  a  Cripes  man  to  look  down  his  nose  at  a  Hell's 
Fire  man.  If  the  latter  were  to  say  BrimstDne  and 
Ashes,  or  Perdition,  it  would  not  even  get  a  raised 
eyebrow  in  polite  society  -  Yet,  the  meaning  is 
exactly  the  same. 

Let's  face  it;  language  belongs  to  those  who  use 
it,  not  to  those  who  would  like  to  regulate  and 
limit  it.  And  if  you  really  want  to  get  down  to 
cases,  it's  not  really  the  words  these  people  are 
gunning  for.  They  are  trying  to  shoot  down  the 
ideas  that  are  expressed  by  words.  And  ultimately 
to  take  away  your  right  and  mine  to  express  them. 

^^      i^p      ^k 

Would  someone  please  explain 

Why  the  hardest  thing  in  the  world  to  get  is  an 
honest  audio  report. 

Why  the  next  hardest  thing  to  get  is  a  rotator 
that  doesn't  quit  during  the  worst  blizzard  of  the 
winter. 

Where  to  find  a  ham  who  is  satisfied  with  your 
S-Meter. 

Why  the  guy  with  the  most  atrocious  banana- 
boat  swing  is  the  most  zealous  opponent  of 
electronic  keyers,  on  the  grounds  that  they  rob 
fists  of  individuality- 

Why  your  XYL  insists  upon  using  the  vacuum 
when  the  signals  are  marginal. 

Why  certain  hams  send  CQ  at  a  swifter  rate 
than  their  ability  to  copy,  and  when  you  match 
their  sending  speed  exactly,  they  request  you  to 
QRS, 

Why  some  ignoramus  breaks,  uninvited,  into 
your  discussion  without  identifying,  and  demands, 
"Why  don't  youse  guys  stop  talkin'  about  all  that 
political  crap?  Dontcha  know  that  controversial 
stuff  is  outa  bounds?  What  are  ya  anyway,  a  bunch 
o^  commies?" 

Why  the  lid  who  starts  calling  CQ  on  your 
frequency  always  says  to  tlie  guy  he  hooks  up 
with,  "We're  getting  QRMM.  Boy,  I  dunno  what's 
happening  nowadays  on  the  ham  bands.  There's 
just  no  courtesy  anymore."  But  don't  get  me 
wrong-...,... J  love  Amateur  Radio!  K2AGZ 


30 


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Check  the  following  features  and  see  why  it's  the  best.  Collins  IF  fitter  for  separating  those  closely 
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cross  modulation*  Automatic  squelch  for  eliminating  noise*  Self-contained  speaker*  OperatK  on 
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receiver.  Additional  channels  available  just  by  plugging  in  another  crystal  at  $4.95  ea.  No  need  to 
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to  175  MHz. 

HOW  TO  ORDER:  The  VANGUARD  FMR-150  is  available  only  direct  from  our  factory.  Include 
remittance  in  full  plus  sales  tax  if  you  reside  in  N.  Y.  Be  sure  to  state  the  6MHz  ^ment  you  will 
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Dept.  H,  196-23  Jamaica  Ave., 


VANGUARD  LABS 


Hollis,N.Y.  11423 


Auto  bandwidth 

The  accompanying  diagram  is  an  auto- 
matic bandwidth  control  circuit  for  the  if 
strip  ot  ham  receiveiSL  It  will  give  a  mioi- 
mum  bandwidth  of  1800  hz^  with  a  signal 
input  at  the  antenna  of  1  uv  and  the 
maximum  if  response  for  signals  greater  than 
1000  uv.  Since  the  choice  of  photo  cell  PR 
governs  the  actual  extremes  I  shall  not  quote 
any  figures. 


VI  emits  Ught  and  is  controlled  by  the 
AVC 

Photo  cell  PR  is  in  series  with  the  Q 
multiplier  set  in  its  minimum  bandwidth 
condition  and  therefore  continually  adjusts 
to  the  signal  tuned.  It  is  quite  effective  for 
weak  signals,  giving  a  better  signal/noise 
ratio.  It  is  operated  by  a  simple  switch. 

The  patent  for  this  device  was  granted  Jan 
uary  4,  1966,  number  3,227,961- 


LEAST 
RESISTANCE 


MAXIMUM 
RESISTANCE 


In  the  actual  unit  many  cells  seeing 
different  parts  of  the  visible  spectrum  were 
tested. 

Since  the  idea  is  simple,  I  will  say  no 
more. 

Roderick  A.  Johnson,  KIPIZ 


I 


I 
I 


73  MAGAZINE 


31 


mm 


Scop 


e 


George  Wilson  WlOU* 
318  Fisher  Street 
Walpole,MA    02081 


rator 


Introduction 

Instrumentation  for  the  amateur  who 
does  his  own  design,  construction  and  repair 
work  has  improved  remarkably  over  the  past 
twenty  years!  It  is  hard  to  imagine  how  we 
tuned  antenna  systems  without  VSWR 
meters  and  forward/reverse  power  meters. 
Most  of  us  were  lucky  if  we  had  a  simple 
volt-ohm- miHiameter.  Those  of  us  who  knew 
what  an  oscilloscope  was  considered  it  far- 
out  for  application  to  our  amateur  problems. 
Today  we  have  a  wide  range  of  instmments 
available,  varying  in  sophistication  from  the 
spectrum  analyzer  ("Panadaptprs"  and 
similar  instruments)  to  gadgets  like  the 
calibrator  to  be  described  in  this  article. 


Ftmctional  Description 

Perhaps  the  most  frustrating  aspect  of 
using  an  inexpensive  oscilloscope  is  its  lack 
of  voltage  calibration.  This  fmstration  can 
be  easily  eliminated  by  the  addition  of  an 
external  calibrator  which  allows  the  signal 
under  test  and  the  calibrating  signal  to  be 
switched  without  disconnecting  and  recon- 
necting the  oscilloscope  leads.  The  calibrator 
produces  square  waves  of  known  voltage 
amplitudes*  With  one  of  these  square  waves 
apphed  to  the  oscilloscope^s  input  terminals, 
the  gain  of  the  oscilloscope  is  adjusted  until 
the   signal    height    on   the    tube  face  is  a 


convenient  number  of  divisions  when 
measured  by  the  reticle  in  front  of  the  tube 
face.  Typically,  a  ten-volt  square  wave  may 
by  applied  and  the  gain  adjusted  such  that 
the  square  wave  is  ten  divisions  high  on  the 
reticle.  Each  division  on  the  reticle  is  then 
equivalent  to  1  volt.  Similarly,  if  a  one  volt 
square  wave  were  appUed  and  the  gain  set 
for  ten  divisions^  each  division  would  re- 
present 0. 1  volts. 


OSCILLOSCOPE   CAUBRATOH 


i:r  isOLATiow 

TftANSrORMEA 


M 


lOK  IW 


SlLtCON 
CTIFIER 

iINT  RECT  I0D3> 


It 


f 


2ENER  DIODE 
10  VOLT  400MW 


9K?i/2W 


IK?  I/2W 


100  ^  1/2  W 


CHASSIS  /77 
GROUND 


2P'4P0S 
NON  ~  SHORTING 


^^HXKTRALAB  PA  OOZ) 


TEST  , 
SIONAL 


f  irTV 
60CPS 


INPUT 
iiCNNG 

POSTS 


OUtWF 
TO 

SCOPE 


^ 


Circuit  Description 

The  calibrator  circuit  (see  circuit  dia- 
gram) consists  of  an  isolation  transformer,  a 
rectifier,  a  Zener  diode  clipping  circuit,  a 
step  attenuator,  and  a  selector  switch.  The 
isolation  transformer  minimizes  the  electric 
shock  hazard.  Note  that  an  electrostatic 
shield  between  the  primary  and  secondary  is 
suggested  to  minimize  the  coupling  of  60 
hertz  hum  into  the  oscilloscope's  input 
circuit.  The  rectifier  reduces  the  sinusoidal 
voltage  across  the  transformer's  secondary  to 
a  "half  sine  wave,"  L  e.,  to  a  half- wave- 
rectified  waveform.  The  clipping  circuit 
further  reduces  the  waveform  to  a  form  very 
close  to  a  squarewave  with  peak-to-peak 
amplitude  of  10  volts.  The  step  attenuator 
provides  outputs  of  1.0  and  0.1  volts;  these, 
and  the  basic  10  volt  square  wave,  may  be 
selected  by  the  switch. 


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Physical  Description 

The  calibrator  is  built  in  a 
2-1/4  X  2-1/4x4  inch  minibox.  The  layout 
of  parts  is  simple  and  not  critical  and, 
therefore,  no  drawings  have  been  included  in 
this  article.  Care  shoidd  be  taken  to  shield 
and  separate  the  test  signal  leads  from  the  60 
hertz  calibration  signal  circuits. 

A  pair  of  banana  plugs  are  mounted  on 
3/4  inch  centers  at  one  end  of  the  minibox. 
These  plug  directly  into  the  oscilloscope's 
input  terminals.  A  pair  of  terminals  similar 


to  the  oscilloscope's  input  terminals  are 
mounted  on  the  other  end  of  the  minibox 
and  are  used  to  connect  the  test  signal. 

The  switch  has  four  positions:  test  signal, 
ten  volts,  one  volt  and  0. 1  volts.  This  choice 
of  calibration  voltages  will  allow  full-scale 
calibration  of  the  oscilloscope  in  the  range 
from  0.1  volts  to  100  volts. 

Conclusion 

The  convenience  afforded  by  this  cali- 
brator makes  it  weU  worth  its  cost  and  the 
time  necessary  to  build  it.  Its  accuracy  is 
governed  by  the  accuracy  of  the  Zener 
diode.  The  diode  specified  in  the  parts  list 
win  give  5%  accuracy  which  is  similar  to  the 
accuracy  provided  by  common  panel  meters* 
Additional  accuracy  is  probably  limited  by 
the  oscilloscope's  deflection  linearity  and 
the  width  of  the  oscilloscope's  trace. 

This  device  will  greatly  simplify  work  on 
both  transistor  and  tube  circuits.  It  makes  an 
oscilloscope  double  as  a  vacuum  tube  volt- 
meter at  minimum  cost  with  the  con- 
venience of  not  having  to  connect  a  separate 
instrument  to  make  voltage  measurements. 

_  ,  .  WIOLP 


OCTOBER    1969 


33 


That  Have   Known  Me 


Robert  Manning  Kl  YSD 
Vfest  Rye,  NH  03891 


"Hey,  you,  you  jerk!  Yeah  you,  the 
ham-operator  dum  dum!''  A  voice  boomed 
out  into  the  morning  stillness  and  assaulted 
my  eardrums  as  I  was  leaving  for  the 
unemployment  office  (I'm  having  trouble 
getting  work  in  my  chosen  profession. 
There's  not  much  call  for  a  human  cannon- 
ball  anymore— especially  since  the  last  time 
out  I  overshot  the  net,  carromed  off  the 
cotton  candy  machine,  which  ran  amuck 
turning  most  of  the  audience  into  a  cluster 
of  Bo  Jangles  looking  for  a  Shirley  Temple, 
landed  smack  on  top  of  the  tatooed  lady, 
turning  her  black  and  blue  and  obhterating 
most  of  her  artwork,  startled  the  fire-eater 
who  hiccoughed  and  set  fire  to  the  bearded 
lady  which  scared  hell  out  of  the  sword 
swallower,  causing  him  to  inadvertantly  re- 
lease the  spring  catch  on  a  Malayan  machette 
thus  performing  not  only  an  auto-appen- 
dectomy, but  much  more  serious  damage. 
To  this  day,  whenever  he  sees  me,  he  kicks 
off  his  high  heels,  lifts  his  skirt  and  tears 
after  me  shouting  all  sorts  of  threats  in  a 
shrill  voice!  I  don't  know  what  his  complaint 
is— they  named  a  sandwich  after  him— sliced 
chicken). 


The  roar  had  emanated  from  one  of  my 
female  neighbors— you  know  the  type— so 
misshapen  and  ugly  that  if  she'd  been  seen 
by  Moses,  there'd  have  been  eleven  com- 
mandments. She  is  the  possessor  of  a  cavern- 
ous mouth'so  large  that,  by  comparison,  a  7 
ply  6:00x16  Goodyear  white  waU  looks  like 
a  licorice-and -peppermint  lifesaver.  *'Do  you 
know/'  she  thundered,  "that  every  time  you 
play  with  that  radio  junk  of  yours,  my  toast 
turns  black  and  I  start  hearing  things?*' 

Remembering  item  No.  32  from  the 
pamphlet,  "How  To  Handle  TVI  Complaints 
With  Tact  and  Diplomacy,"  I  deported 
myself  Hke  any  other  mature,  gentlemanly, 
self-respecting  ham  would  have  done  under 
similar  circumstances.  I  jingled  the  change  in 
my  pockety  brushed  back  my  Alan  Ladd 
forelock,  straightened  my  tie,  wound  my 
wrist  watch,  picked  my  nose,  checked  my 
zipper  and,  with  a  yeU  of  "Blow  it  out  your 
smokestack  you  beady-eyed  daughter  of  an 
illegitimate  pickpocket!'',  T  hurled  the 
largest  rock  I  could  find  at  the  big-mouthed 
old  bat! 

Unfortunately,  I  missed  the  old  bag— my 
knuckleball  just  isn't  what  it  used  to  be—and 


34 


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hit  her  pet,  "Heinrick/*  New  England*s 
largest  living  carnivore— a  German  shep- 
herd— an  animal  with  the  mentality  of  a. 
citizen  bander,  the  disposition  of  a  newly 
appointed  '*00"  and  singularly  devoid  of 
any  form  of  mirth  whoM  obviously  read 
Mein  Kampf  and  bore  a   grudge  for  losing 

WWIL 

Taking  refuge  in  my  car,  I  watched  the 
beast  eat  my  fender,  headliglit,  rear-view 
mirror  and  top  it  off  with  my  two-meter 
halo. 

Finally,  fully  gorged,  fully  sated  and 
having  vented  his  spleen,  he  started  back 
towards  his  owner.  I  couldn't  resist  one 
parting  reparte  as  I  drove  off  in  my  now 
fender-light-antennaless  car,  and  I  said, 
speaking  to  the  dog  but  in  a  voice  loud 
enough  for  the  neighbor  to  hear,  "See  ya, 
Heinrick,  and  tell  your  *mother'  (with  all 
which  that  implied)  that  if  she  keeps  hearing 
things,  the  men  in  the  Good  Humor  uni- 
forms with  the  snow-white,  crepe-soled 
sneakers  are  going  to  certify  her  as  a  class 
"A"  goober  and  wheel  her  off  in  a  wire  mesh 
basket  wrapped  in  a  wet  bed  sheet!" 

As  1  rounded  the  corner  on  two  wheels— 
chortUng  and  wondering  where  I  was  going 
to  get  a  fender  for  a  '36  Hudson  Terraplane, 
I  heard  a  loud  crash  from  the  rear  of  the  car. 
Later  investigation  showed  that  1  had  solved 
one  of  the  old  broad's  problems.  If  she 
wanted  any  more  toast— black  or  other- 
wise—she'd have  to  run  an  extension  cord  all 
the  way  to  my  license  plate  and  trailer  hitch. 

This  is  but  one  of  the  800  LT.VJ,  cases 
that  1  had  been  involved  in  during  a  five-year 
tour  at  a  trailer  park  (ofttimes  referred  to  as 
a  **horizontal  high  rise"  or  **an  instant 
slum").  [Now,  if  the  type-setter  has  kept  out 
of  the  Haig&Haig,  isn*t  hung  over  and  hasn't 
been  distracted  by  a  passing  micro-mini 
skirt,  as  1  suspect  must  have  happened  in 
three  of  my  last  four  articles,  since,  in  each 
case,  a  key  word  was  changed,  turning  an 
otherwise  humorous  paragraph  into  a  mean- 
ingless jumble  of  unconnectable  words,  you 
will  notice  that  I  said  LT.V.LI 

ITVl  is  a  little  complicated  to  define.  The 
initials,  of  course,  stand  for  Imaginary  Tele- 
Vision  Interference,  but  it  goes  much  deeper 
and  is  more  profound  than  simple  imagina- 
tion on  the  part  of  an  arbitrary  or  isolated 


television  viewer, 

ITVI  is  the  product  of  the  bigotted  and 
stagnated  mind  of  ''The  VWIOT/'  The 
Vidiot  (Video  Idiot)  has  become  an  ever 
growing  ethnic  group  within  our  society- 
moving  into  "1984"  and  "Big  Brother" 
twenty  years  premature.  He  is  totally  mes- 
merized by  that  flickering  rectangular  eye. 
His  entire  thought  processes,  eating  habits 
and    even    his    sex   life   are    controlled   by 

CYCLOPS!  .  .  .  CYCLOPS  all  hail  the  one- 
eyed  God!  .  .  .  "Johnny  has  to  be  in  bed  by 

half  past  the  Flying  Nun'*  ..•**!  want  you 
home  before  The  FBI"  ,  .  -  "The  roast  wUl 
be  done  about  quarter  to  ADAM-12  ,  .  . 

(One  Vidiot  1  know  of  became  so  des- 
pondent when  his  set  was  removed  for 
repairs  that  his  wife  was  forced  to  light  up 
the  aquarium,  sit  him  down  in  front  of  it 
and  keep  reassuring  him  that  it  was  a  Jacques 
Cousteau  Special.  When  that  wore  off,  she 
mixed  him  a  "Missing  TV  set  cocktail"-'Six 
parts  prune  juice  to  one  part  gin -the  Vidiot 
knew  the  TV  was  missing,  but  he  was  too 
damned  busy  to  really  care,) 

The  Vidiot  comes  in  two  forms.  The  type 
that  has  jumped  from  infancy  to  senihty 
completely  omitting  maturity,  and  the  type 
that  exists  in  a  limbo  state  of  arrested 
pubescence! 

If  you  felt  the  urge  for  creative  analogies, 
you  could  call  them  Vidicon  Buddhists— 
differing  from  the  "navel  contemplating" 
Buddhists  only  so  far  as  the  location  of  the 
navel  to  be  contemplated  is  concerned.  The 
Vidiot  searches  for  Nirvana  through  a  trans- 
planted electronic  and  transistorized  navel 
installed  in  a  cabinet,  but  is  nonetheless 
connected  to  it  by  an  ivisible  optical/audi- 
tory umbilical  cord. 

Imaginary  interference  can  be  conjured 
up  in  the  mind  of  a  vidiot  at  the  slightest 
provocation  (especially  during  one  of  his 
favorite  programs— like  BOZO  or  Dark 
Shadows  or  the  Late  Night  Movie  showing, 
"The  Oyster  that  swallowed  Mt*  McKin- 
ley"),  and  at  the  first  flicker  he  can  be 
expected  to  leap  into  the  air  with  a  rousing, 
'^HUZZAH!",  whip  his  bumbershoot  out  of 
the  elephant  foot,  slam  his  purple  pith 
helmet  on  his  head,  yank  open  the  door, 
and,  like  some  modern  Don  Quixote, 
wearing  only   the  CD  pith  helmet,  jockey 


36 


73  MAGAZINE 


p 


shorts  and  mucklucks  and  waving  the  bum- 
bershoot  in  one  hand  and  a  TV  Guide  in  the 
other,  race  into  the  night  screaming,  "I 
know  you're  out  here— my  TV  is  flickering!" 

Where  do  vidiots  come  from  and  why  do 
they  hang  to  this  outmoded  belief?  This 
fallacy -like  burying  a  hank  of  hair  and  a 
fingernail  at  the  full  of  the  moon  to  rid 
yourself  of  warts,  eating  raw  eggs  to  improve 
virility,  or  buying  Playboy  "just  for  the 
articles"  has  been  passed  on  from  vidiot  to 
vidiot— stupidity  is  not  contagious,  but  to 
not  believe  would  mean  that  Cyclops  is  not 
infallible. 

TV  repairmen  live  in  constant  terror  of  a 
call  from  a  vidiot  where  the  set  will  have  to 
be  removed.  The  "sophisticated"  repairman 
comes  armed  with  COPE,  NERVINE  and 
MILLTOWNS;  the  "average'*  repairman 
simply  brings  along  a  leather  strap  or  a  bullet 
for  the  vidiot  to  bite  on  while  the  repairman 
pries  his  fingers  off  the  fine  tuning  knob;  but 
the  uncouth  repairman  simply  walks  in  and 
bludgeons  the  vidiot  with  the  stubby  end  of 
an  Indian  club. 

An  IT VI  or  Vidiot  call  can  almost  always 
be  distinguished  within  the  first  few  words 
of  the  conversation.  The  vidiot  has  a  ten- 
dency to  "gild  the  lily,"  the  voices  he 
hears  always  **sound"  like  a  ham,  the  lines 
he  SQes  always  "look"  like  the  Unes  of  a  ham, 
and  more  often  than  not  he*ll  claim  that  he*s 
hearing  Morse  code. 

You  know  this  "frograouth"  wouldn't 
know  Morse  code  if  Marconi,  Samuel  B. 
Morse  and  Hiram  Percy  Maxim  were  all 
simultaneously  hammering  out  **CQ  DX''  on 
the  frontal  lobe  of  his  cerebrum  with  an  axe 
handle,  a  No.  9  iron,  and  a  croquet  mallet 
respectively. 

It  was  a  common  J  rather  than  uncom- 
mon, thing  to  be  interrupted  during  snoozes, 
showers  and  other  nefarious  activities  by  the 
ringing  of  Alexander  Graham  Bell's  dubious 
contribution  to  moderna.  (Incidently,  I  have 
definitely  established  that  the  first  phone 
conversation  was  not  "Mr,  Watson,  come 
here  I  want  youf*  but  rather  a  call  from  the 
downstairs  neighbor  complaining  that  Mr. 
Bell's  infernal  machine  was  interfering  with 
the  operation  of  the  neighbors'  VICTROLA, 
making  Enrico  Caruso  sound  like  a  bari- 
tone!) 


When  the  phone  rings  for  a  TVI  call^  as 
some  of  you  are  undoubtedly  aware,  it 
seems  to  possess  a  special  tonal  quality— sort 
of  a  cross  between  a  death  knell  and  the 
noise  your  car  makes  30  minutes  after 
you've  mailed  off  the  last  payment. 

Picking  up  the  phone  on  these  occasions 
I*d  say  in  my  most  cordial  manner,  "Hello 
there!  Whom  have  I  the  pleasure  of  addres- 
sing over  this  veritable  miracle  of  electrical 
science?'*  After  a  slight  pause,  a  voice  would 
rumble  back^  **Listen  you  wacky  nut— you're 
on  my  TV  and  if  you  don't  stop  it,  I'm 
coming  up  there  and  whomp  you  on  the  top 
of  the  head  with  a  2x4  until  you're  bowleg- 
ged  from  the  neck  down!'' 

*^Ah,  forsooth,"  said  I,  remembering-be 
nice,  be  calm,  "If  you  wiU  tell  me  where  you 
reside  and  abide^  Til  come  down  and  take  a 
look  at  your  TV,  for,  verily,  I  haven't  had 
my  rig  on  in  almost  a  fortnight!" 

'*Whazzat?  Whazzat?   What  the  hell  are 

you  talking  about?  Huh?  Huh?" 

"I  said,  where  do  you  hve,  stupid?" 

Living  as  I  did  in  a  trailer  court  where 
your  furthest  neighbor  was  as  close  as  100 
yards  and  where  there  were  over  80  TV's 
within  the  area,  I  thought  it  a  good  practice 
to  visit  anyone  with  a  complaint— just  to 
keep  good  will  up  and  rumors  down.  In  all 
800  cases,  I  never  had  a  bona  fide  case  of 
TVI  attributable  to  me.  This  gave  me  a 
first-hand  look  at  a  continuing  flow  of 
vidiots  wliich  defies  description.  At  one  time 
I  thought  that  I  must  possess  some  inner 
personal  magnetism  that  attracted  the  luna- 
tic fringe  like  ZSA  ZSA  attracts  and  accumu- 
lates jewelry. 

With  each  call,  I  would  dutifully  don  my 
**technicaHype"  coat— actually  a  sanitation 
engineer's  coat  which  I'd  appropriated  at  a 
Trailways  bus  depot— and  picked  up  my 
Interference  Portmanteau,  which  contained 
on  one  side  TVI  brochures,  high  pass  filters, 
wave  traps  and  some  test  equipment  (aU 
about  as  useful  in  ITVI  cases  as  the  "pill"  is 
to  an  octogenarian).  On  the  other  side,  I 
carried  my  Vidiot  Analytical  Conglometer, 

In  order  to  understand  the  V,A.C.,  you 
must  first  understand  the  mental  workings 
of  the  Vidiot-  He  will  not  install  a  high-pass 
filter  or  a  wave  trap,  even  though  they're 
free.  He  wants  someone  or  something  he  can 


OCTOBER    1969 


37 


blame,  hate  and  rant  about.  The  V.A.C,  is 
my  own  design  and  is  flexible  enough  to 
handle  most  vidiots. 

The  Vidiot  Analytical  Conglometer  is 
housed  in  a  5x6  mini  box*  There  are  only 
three  basic  parts  to  it:  (1)  A  small  variac 
coupled  to  an  ac  meter  and  ac  plug-  The 
meter  is  labeled  in  five  stages.  Depending 
upon  the  vidiot  you  are  dealing  with,  you 
can  adjust  your  conglometer  to  read  the 
cause  of  his  problems  as  being  A,  the 
weather;  B,  the  bomb;  C;  the  Russians;  D, 
rockets;  and  E,  UFO's*  (2)  The  second  part 
is  a  3"  speaker  with  alligator  clips  to  parallel 
to  the  output  of  the  TV— if  you  can  cause  a 
feed  back  squeal^  you  can  make  him  believe 
anything,  (3)  Appearance—the  conglometer 
has  got  to  look  impressive.  I  have  a  rotatable 
tea  strainer  plumb  on  top  and  a  two-section 
auto  antenna  on  the  side,  plus  a  number  of 
lights,  knobs  and  other  assorted  junk, 

I  cannot  possibly  recount  all  800  ITVI 
cases,  but  I  can  give  you  a  typical  incident. 

Clad  in  my  technician-type  coat,  I  jour- 
neyed to  the  home  of  the  complainer.  My 
eyes  had  become  accustomed  to  the  dark  by 
the  time  I  arrived,  (Vidiots  always  call  at 
night.)  So  as  I  entered  the  dark,  murky 
interior,  I  could  easily  make  out  the  semi- 
prostrate  form  of  the  vidiot  with  his  hair 
hanging  down  into  his  can  of  Black  Label 
which  he  clutched  as  if  it  would  take  a  skin 
graft  to  remove  it. 

I  was  immediately  accosted  by  two  ani- 
mal forms.  The  first,  a  futwe  vidiot -a  sticky 
jam,  tar-  and  glue-fingered,  curtain-climbing, 
crumb-grabbing,  rug  rat  that  attached  itself 
to  my  leg  like  Sinbad's  "old  man  of  the  sea," 
shrieking  and  screaming  something  totally 
unintelligible  (all  vidiots  have  one  or  two  of 
these  around  the  house;  and  the  second  was 
the  smallest,  nastiest^  noisiest,  most  pop- 
eyed  Chihuahua  that  Vd  ever  seen, 

"Clem/*  came  a  voice  from  the  kitchen, 
"tell  the  man  he  won't  bite!" 

"The  dog  or  kid,  lady?''  I  asked.  "I  don't 
mind  that  bug-eyed  canine  chomping  on  my 
shin  bone,  but  if  that  kid  so  much  as  breaks 
the  skin,  I  want  a  tetanus  shot  right  away!" 

About  this  time,  Clem,  the  vidiot,  de- 
meaned himself  to  notice  me,  and  brushing 
the  ashes  and  crumbs  from  his  gravy  and 
beer  stained  "T**  shirt,  he  looked  up  but 


4(' 


CC* 


didn't  get  up,  and  in  the  vernacular  of 
vidiots,  he  said,  "Dahh,  so  you're  the  ham 
bum  that's  been  screwing  up  my  TV,  huh?" 

"You  tell  him,  Qem!"  came  the  voice 
from  the  kitchen. 

'Took  neighbor,"  I  said,  trying  desper- 
ately to  drop  the  portmanteau  on  top  of  the 
dog  while  trying  to  get  a  death  grip  on  the 
40  pounds  of  animated  garbage  who  was 
now  not  only  trying  to  get  his  gooey  hand 
into  my  pocket,  but  also  doing  his  level  best 
to  break  every  bone  in  my  instep.  ''1  came 
down  to  see  if  I  could  give  you  a  helping 
hand.  I  haven't  had  my  rig  on  in  several 
days— now  where's  the  TV  set?" 

Don't  gimme  that  crud!"  he  said. 
'TeU  him   off,   Clem,"  came   from   the 
kitchen. 

"I  know  all  about  you  hams  ,  .  .  yeah,  we 
had  one  of  you  guys  back  in  Oklabraska— 
soon  as  the  old  man  left,  the  old  lady'd  get 
on  there  and  start  making  dates  all  over 
town.  Then  the  kids  would  get  on  there  and 
talk  to  each  other,"  he  grumbled  officiously, 

"Tell  him,  Clem!"  came  the  voice  from 
the  kitchen, 

"And  another  thing,"  he  said,  turning  to 
get  another  beer  (I  seized  this  opportunity 
to  Norden  Bomb  sight  the  goddamn  dog  and 
surreptitiously  twist  the  kid's  ear  a  full  1 80 
degrees— both  went  screaming-louder,  if 
that's  possible-into  the  kitchen),  "That  big 
antenna  of  yours  is  sucking  all  the  power  out 
of  my  set/' 

"Tell  him  off,  Clem!"  came  the  voice 
from  the  kitchen  (unbeUevably  over  the 
wailing  din  of  a  scrunched  dog  and  a 
twisted-eared  kid). 

"You  suppose  you  could  show  me  the  TV 
set  and  keep  the  commentary  for  later,"  I 
said, 

"Smart  Bustard,  huh?  That's  it  over  in 
the  corner.  Maw  had  it  for  15  years  and 
we've  had  it  for  5,  Never  had  any  trouble 
except  for  you  hams,"  he  said,  indicating  a 
large,  brown  crate  about  the  size  of  a 
restaurant  freezer  with  what  appeared  to  be 
a  broken  coat  hanger  with  tinsel  hanging  off 

it. 

"Where's  the  screen?" 

"Right  there,  that  six  inch  hole,  see  the 
flickering?  You're  doing  that.  See  what 
you*re  doing?  Huh?  Huh? 


38 


73  MAGAZINE 


*TeII  him  off,  Clem/'  came  from  the 
kitchen  • 

"Fm  standing  right  here,  so  what  can  I  be 
doing?  You  ever  tliink  about  having  *er 
stuffed?" 

'The  TV?" 

"No,  that  voice  from  the  kitchen!'* 
Ducking  a  beer  can,  I  continued,  "Buddy, 
this  set  is  20  years  old  and  the  only  way 
youVe  gonna  get  a  picture  on  it  is  with  the 
help  of  Timothy  Leary!" 

"Who's  he?  Another  screwy  hara?" 


**Tell  him,  Clem/'  came  from  the  kitchen. 
"Ya  know,  friend,"  I  said,  "I  could  solve 

all  your  problems  just  by  inserting  a  small 

piece  of  lead  in  your  left  ear!" 

"That  would  fix  everything  up,  huh?" 
"As  far  as  I'm  concerned,  it  would!" 
"How  would  you  insert  the  lead?" 
"With  a  .38  Smith  and  Wesson  .  ,  . 

_.K1YSD 

(Type-setter's  note:  I  am  not  distracted  by  micro^ 
mini  sktts.  However,  the  editor's  Bermuda  shorts 
occasionally  catch  my  eye  ...  J 


Mobile  Transmitter  Heater  Switching 

In  amateur  FM  communications  opera- 
tion long  periods  are  spent  monitoring  a 
sometimes  vacent  channel  with  relatively 
few  transmissions.  When  I  converted  an  old 
rig  to  put  in  my  car,  it  soon  became  appar- 
ent that  keeping  the  transmitter  filaments 
hot  would  result  in  a  considerable  power 
waste  from  the  already  overtaxed  car  bat- 
tery. The  receiver  uses  many  filament  type 
low  current  tubes,  but  the  transmitter  heat- 
ers waste  power-  The  rig  is  remotely  con- 
trolled in  the  trunk  by  a  control  head  and 
connecting  cable.  No  means  was  provided  to 
allow  separate  switching  for  the  transmitter 
heaters. 

To  solve  this  problem  I  devised  a  switch- 
ing method  that  allowed  the  desired  control, 
but  with  no  extra  switches  or  cables  on  the 
control  head.  The  scheme  is  shown  in  Fig. 
1-  When  the  receiver  is  turned  on,  the  trans- 
mitter  filaments  will  not  be  turned  on  until 
the  microphone  push-to-talk  button  is  push- 
ed. When  the  button  is  pushed,  the  T—R  re- 
lay and  Kl  will  be  activated.  As  Kl  pulls  in, 
it  in  turn  turns  on  K2.  One  set  of  contacts 
on  K2  activates  the  transmitter  heaters,  and 
the  other  set  of  contacts  holds  K2  in  contin- 
uously. When  you  wish  to  turn  the  transmit- 
ter heaters  off,  simply  momentarily  turn  the 
receiver  power  off  and  the  voltage  to  K2 
wHl  be  gone.  The  receiver  can  then  be  turn- 
ed on  without  activating  K2,  unless  the  push 
to  talk  switch  is  activated. 

In  my  case^  Kl  was  not  necessary  because 
the  T-R  switch  had  an  extra  pair  of  contacts. 
Be  sure  that  the  contacts  of  K2  can  handle 
the  current  that  your  transmitter  requires. 
Six  volt  relays  can  be  used  with  series 
resistors  calculated  from  Ohm's  Law,  al- 
though this  will  add  to  current  drain. 

This    system   can   increase   power  waste 


+12VDC  FROM  HECEtVER 


EXtSTiNG  TR 
Rf  LAY  COL 


r— — -  F" 


TO  TRANS 
HEATERS 
— O 


CONTROL 
CABLE 


MICROPHONE 
RTT  SWITCH 
IN  CONTROL  HEAD 


Fig.  1,  Power  saving  heater  controL 


during  transmission  because  of  the  relay  cur- 
rent, and  some  people  may  not  like  to  wait 
for  the  transmitter  to  warm  up.  However^p 
this  was  a  good  solution  in  my  case  because 
of  my  style  of  operating  and  limited  activity 
on  our  local  channel.  If  you  don't  like  to 
waste  power,  and  you  don't  like  to  run  ca- 
bles and  install  switches  where  there  is  no 
room  for  switches,  this  system  may  solve 
your  problems  too. 

Clifford  Klinert,  WB6BIH 


MOVING? 

Ev^ry  day  we  get  a  handful  of  wrappers 
back  from  the  post  offrce  with  either  a  change 
of  address  on  them  or  a  note  that  the  sub- 
scriber has  n^oved  and  left  no  addresSt  The 
magazines  are  thrown  out  and  just  the  wrap* 
per  returned-  Pleas©  don't  expect  us  to  send 
you  another  copy  if  you  forget  to  let  us  know 
about  your  new  address.  And  remember  that 
tfl  this  day  of  the  extra  rapid  computer  it 
fakes  six  weeks  to  make  ^n  address  change 
instead  of  the  few  days  it  used  to  when  we 
worked  slowfy  and  by  hand. 


OCTOBER    1969 


39 


Don  McCoy  WA^HKC 
42S0Hoyi  Court 
Wheat  Ridge  CO  80033 


The  Protector 


Here  is  a  practical  circuit  to  have  around. 
It  can  be  used  for  protecting  your  ham  gear 
or  perhaps  your  expensive  new  color  TV,  A 
fellow  at  work  was  telling  me  how  his  house 
power  went  on  and  off  three  times  in  rapid 
sucession  during  a  storm.  He  and  his  family 
were  watching  their  color  TV  at  the  time. 
After  the  power  settled  down,  his  TV  didn't 
work  and  it  cost  something  like  $130  to  get 
it  all  straightened  out*  This  got  me  to 
thinking  about  what  such  an  occurence 
could  do  to  my  new  solid  state  color  TV. 

The  Protector  is  what  I  came  up  with. 
Here's  how  it  works: 

When  1 1 5  volts  ac  is  available  at  the 
plug,  and  the  fuse  is  good,  the  Reset  Ready 
light  will  come  on  through  pins  2  and  the 
normally  closed  pins  5  and  8.  Then  you 
press  the  momentary  Reset  pushbutton.  This 
operates  the  relay  by  putting  115  volts 
across  pins  7  and  2^  which  is  the  relay  coil. 
When  the  relay  operates,  the  Reset  Ready 
light  goes  out  due  to  pins  5  and  8  opening. 
Pin  8  closes  to  pin  6,  which  is  wired  to  pin  7 
and  the  relay  "locks  up"  through  its  own 
contacts  and  stays  operated  even  when  the 
momentary  pushbutton  is  released.  The  115 
volts  for  the  output  receptacle  is  taken  from 
pins  6  and  2  which  are  in  parallel  with  the 
coil  The  "Thyrector"  across  the  output  is  to 
limit  any  surges  or  transients  in  the  house 
current. 

If  the  power  should  go  off  or  dip  to 
about  85-90  volts  on  my  particular  one,  the 
relay  will  drop  out,  opening  pins  6  and  8. 


Now  even  if  the  power  comes  right  back  on, 
there  is  no  path  to  energize  the  coil  or 
supply  power  to  the  output  receptacle.  The 
circuit  will  stay  this  way  unli!  the  reset 
button  is  pushed. 


RESET 
READY 


Frg.   1,     Diagram  of  the  protector  using  a 
G.E.  thyractof.  Ho.  6RS20SP606. 


1  used  a  Potter  &  Brumfield  KRPllAG 
because  I  had  one  around.  Just  about  any 
single-pole  double-throw  relay  which  has  the 
contact  rating  that  you  need  will  do.  None 
of  the  parts  are  critical.  The  '*Thyrector" 
and  Reset  Ready  light  are  kind  of  an 
optional  item.  Depending  on  your  junkbox 
and  scrounging  ability,  the  whole  thing 
shouldn^t  cost  more  than  a  couple  of  bucks. 

I  have  mine  between  the  color  TV  and 
the  outlet  now^  and  it  has  been  working  fine. 

.,  .WApUKC 


40 


73   MAGAZINE 


NOW 


AT  YOUR  DEALERS 


Buy  your  new  GT-550 
before  November  1  st  - 

Get  the  $29.95  VOX 

ACCESSORY  FREE! 


YouVe  heard  about  this  fabulous  Galaxy  GT-550,., maybe 
you've  even  had  an  opportunity  to  sit  down  and  try  one  at  your  Dealer's 
or  a  fellow  Ham's  place.  Sooner  or  later  you  figure  you're  going  to  ov^n 
one  — wellj  NOW's  the  time!  During  the  month  of  October  all  Galaxy 
Dealers  are  giving  away  a  VOX  Accessory  with  every  GT-550  sold.  But 
if  youVe  going  to  get  one  — act  now,  your  order  has  to  be  in  before 
November  1st,  1969! 


Your  Bonus  Gift  for  buying 
in  the  Month  of  October! 

vox  ACCESSORY  -  VOX35C 


Completely  solid-state  and  instant  plug-in  (internally) 
on  the  GT-550  chassis.  Three  controls  allow  full-range 
settings  for  "vox  gain*\  **anti-vox  gain'*  and  "'time'* 
delay.  Controls  may  be  adjusted  from  outside  cabinet. 
Regularly  sells  for  829,95, 


I 


OFFER  GOOD  AT  ALL  GALAXY  DEALERS 


L.  B.  Cehik  W4RNL 
245  Morning  View  Drive 
Athens^  GA  30601 


Slower  Tuning  Rates 

for    Older  Receivers 


After  the  oscillator  has  been  stabilized, 
the  front  end  sensitized,  and  the  // crystal- 
Ezed,  older  receivers  still  lack  a  feature 
which  makes  the  newer  products  attractive 
despite  their  cost.  That  feature  is  a  slow, 
smooth  tuning  rate  that  allows  one  to  tune 
across  and  with  the  signal  rather  than  by  it. 
Modern  receivers  have  tuning  rates  varying 
from  ten  to  25  khz  per  revolution  of  the 
dial.  In  addition,  they  are  free  of  backlash 
and  have  that  sraooth-as-velvet  feeL  Touch  is 
part  of  what  sells  the  browsing  ham  on  the 
display  model  in  the  radio  shops. 

A  couple  of  years  ago,  W7ZC/W5CA 
published  an  idea  for  slowing  down  the 
tuning  rate  of  the  Drake  2-B.  Basically,  he 
mounted  a  Jackson  Bros,  drive  externally  on 
the  p^nel  of  the  2-B,  using  the  holes  already 
there  for  panel  screws.  Thus,  he  could 
replace  the  original  dial  whenever  he  sold  the 
receiver  without  leaving  any  tell-tale  signs  of 
his  modification.  To  add  the  drive,  all  he 
needed  were  a  plate  to  mount  it  on  and 
some  L  brackets  to  anchor  the  plate  to  the 
panel.  The  idea  is  adaptable  to  almost  any  of 
the  older  receivers  around  and  wiU  give  a 
truly  modem  tuning  rate  plus  the  back- 
lash*free  velvet  feel  that  comes  from  ball 
bearing  verniers. 

Since  there  are  still  plenty  of  older 
receivers  around  just  waiting  for  modificat- 
ion, the  original  idea  could  stand  some 
updating.  It  had  a  couple  of  drawbacks.  With 
the  2-B,  for  example,  moving  from  40,  20. 
or  15  to  80  or  10  meters  means  shifting  the 
dial  from  one  end  of  the  scale  to  the  other • 
It  takes  a  while  at  7  khz  per  revolution  to  do 
this.   In  fact,  one  could  miss  a  ten  meter 


opening  while  getting  to  the  left  end  of  the 
scale.  Secondly,  the  W7ZC  mounting  pre- 
cludes use  of  the  tuning  dial  scale.  Although 
calibration  of  the  theorectically  40  khz  scale 
was  not  accurate  because  the  oscillator  was 
not  linear,  the  scale  was  useful  for  logging 
purposes  when  one  needed  to  find  a  station 

again* 

By   revising   the   mounting  scheme   and 

chosing  an  appropriate  dial  to  replace  the 
original,  it  is  possible  to  overcome  both 
flaws.  In  fact,  one  could  even  add  a  logging 
scale  to  receivers  not  already  having  one. 
With  a  little  practice,  interpolation  of  frequ- 
ency to  tenths  of  a  khz  is  possible  and 
practicaL 

The  first  job  is  to  find  a  dial  that  will 
pernoit  the  use  of  both  the  6-to-l  reduction 
and  the  straight-through  features  of  the 
Jackson  drive.  That  part  is  easy.  The  Galaxy- 
transceivers  and  the  WRL  Duobander  use  a 
dial  which  internally  holds  a  Jackson  vernier 
unit.  If  you  order  one  or  the  other  from 
WRL  as  replacement  parts,  make  sure  you 
onler  all  the  pieces  and  ask  for  the  hardware. 
They  didn't  send  the  little  2-56  screws  to 
fasten  the  straight-through  dial  to  the  ver- 
nier, but  perhaps  this  was  an  oversight.  The 
difference  between  the  Galaxy  and  the 
Duobander  dials  is  that  the  former  has  a 
logging  scale  already  scribed  on  the  outer 
dial.  If  your  receiver  does  not  already  have 
such  a  scale,  this  dial  just  might  fill  the  bill. 
You  might  also  want  to  get  the  little  plastic 
piece  that  serves  as  a  setting  marker.  Since  I 
have  a  2-B,  I  ordered  the  Duobander  knobs. 

Before  showing  how  to  mount  the  new 
dial,  I  should  warn  that  anyone  used  to  a 


42 


73  MAGAZINE 


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HIGHEST  TRADES!  NO  ONE  ANYWHERE  will  beat  our  deal! 
We  will  TOP  any  advertised  or  written  offer  from  any  other  dealer. 
We  trade  on  both  new  and  used  equipment  and  we  service  what 
we  sell.  Instant  credit  on  both  new  and  used  equipment.  General 
Electric  revolving  charge  and  Master  Card  Credit. 

AMATEUR -WHOLESALE  ELECTRONICS 

A  DIVISION  OF 


InrcmaUimal  Elect nmk  Svsrem^.  fnv. 


280  ARAGON  AVEIMUE,  CORAL  GABLES,  FLORIDA  33134 


Cable  "IIMTE 


rt 


305-444 


ort  orders  our  specii 


large  tuning  knob  will  find  the  two-speed 
dial  awkward  at  first.  It  takes  two  fingers  to 
turn,  and  the  straight-through  takes  effort, 
since  it  has  to  move  the  little  knob  at  six 
times  the  speed.  It  is  a  case  of  mechanical 
disadvantage.  No  more  one-finger  spinning 
from  one  end  of  the  band  to  the  other.  But 
the  whole  point  of  the  two  speed  dial  is  to 
be  able  to  get  to  the  part  of  the  band  which 
interests  us  and  then  to  have  really  fine 
tuning. 

A  tip  on  tuning  technique:  don*t  tune 
overhand  •  It  will  tire  you  out  in  a  few 
minutes.  If  the  dial  is  low  enough^  rest  the 
back  of  your  wrist  and  hand  on  the  table 
and  tune  underhand.  The  technique  gives 
you  smooth  tuning  and  a  precise  feel.  Your 
hand  and  arm  muscles  work  only  at  tuning 
(which  takes  little  effort)  instead  of  tuning 
plus  supporting  the  arm  and  hand  (which 
takes  a  lot  of  effort).  Little  things  make  the 
difference  between  pleasant  operating  and 
tiring  battles. 

With  the  WRL  dial,  the  whole  assembly 
can  be  mounted  closer  to  the  panel  than 
W7ZC  described.  The  Jackson  drive  extends 
only  about  a  32nd  beyond  the  dial*  Using 
the  sketches  as  a  guide ^  mount  the  dial  and 
drive  on  a  plate  the  same  diameter  as  the  dial 
on  one  side,  and  as  long  as  necessary  on  the 


CABINET 


-6-32 

SET   SCRIlf 
HOLC 


other.  The  rounded  side  allows  you  to 
mount  a  calibration  scale  behind  the  dial, 
which  is  about  the  same  diameter  as  the 
original  2-B  dial.  Since  the  plate  is  needed 
only  to  prevent  rotational  movement  (the 
shaft  does  the  main  supporting  job),  it  need 
not  be  heavy  or  large.  Eighteen  guage  alumi- 
num or  slightly  thicker  bakelite  is  fine.  For 
the  2-B,  I  cut  a  second  piece  that  crosses  the 
extension  as  a  T  in  order  to  fit  the  panel 
holes  available.  Cutting  the  original  as  a  T 
would  work  just  as  well. 

The  two-piece  version  has  an  advantage: 
it  allows  final  alignment  so  that  everything 
turns  smoothly.  It  is  a  good  idea  to  drill  aU 
screw  holes  in  a  slot  shape  and  to  let  the 
screws  and  lockwashers  do  the  job  of  hold- 
ing things  in  place.  No  matter  how  carefully 
I  measure,  I  am  always  a  bit  off  with  the 
drilL  After  getting  fed  up  with  the  modifi- 
cation because  the  drive  would  bind^  I 
realized  that  it  wasn't  lined  up  properly.  The 
slots  let  me  tighten  the  drive  to  the  shaft 
first  and  then  align  the  plates  to  it.  Now  the 
drive  works  as  smootlily  as  without  any 
load. 

By  using  4-40  screws  (which  fit  through 
the  sheet  metal  screw  holes  without  reaming 
them  out)  and  a  bunch  of  extra  nuts  I  had 
lying  around,  I  solved  the  spacer  problem.  1 


FIBCR   WASHER 


^g  SPACER 


CHASSIS 


Z    5FEED  OiAl.-^ 


6-32     NUT,  BOLT, 
AND  LOCKWASHER 


I  KHZ    SCALE 

PANEL 


FRQMT    V;EW 


SlOe    VtEW 


•jj_  0  0.-  !^tD.  WASHERS    OR 
OTHER    SUITABLE   FRICTON 


CHASSIS 


^g  SPACER 


FIBER  WASHER 
(ALREADY    THERE) 


Fig.  1\  Mounting  of  plates  and  two-speed 
d?aE/drive  as  applied  to  the  Drake  2-B  re- 
ceiver. Modify  as  required  by  the  particular 
receivdf  being  adapted  for  a  slower  tuning 
rate. 


BOTTOtI    VIEW 


44 


73  MAGAZINE 


recommend  3/8  inch  spacers,  but  1/4  inch 
spacers  with  solid  washers  on  top  and  fiber 
or  felt  washers  against  the  panel  to  prevent 
marring  will  do  as  well.  For  other  receivers, 
the  size  of  the  spacer  will  depend  on  how  far 
out  from  the  panel  the  dial  shaft  extends. 

The  shaft  of  the  drive  requires  a  half  to 
5/8  inch  hole.  I  used  the  larger  size  because  I 
wanted  to  keep  the  2-B  calibration  plate.  It 
is  kept  turning  by  a  spring  on  the  dial  shaft 
pushing  against  the  plate  which  in  turn 
pushes  against  the  dial.  Since  the  Jackson 
drive  does  not  push  onto  the  shaft  as  far  as 
the  original  dial,  there  is  space  to  be  filled 
up.  Tubing  with  an  inside  diameter  of  1/4 
inch  of  either  metal  or  plastic,  or  even  a  gob 
of  electrical  tape  wound  around  the  shaft 
will  do  nicely.  The  aim  is  to  keep  the  plate 
turning  with  dial  rotation  but  to  allow 
freedom  enough  to  reset  it  at  will.  I  had  a 
large  number  of  1/4  inch  inner  and  9/16  inch 
outer  diameter  washers  which  sUd  very 
nicely  onto  the  shaft.  Just  choose  the  right 
number  for  the  shaft  length  to  be  filled  up. 
The  advantage  of  the  washers  is  that  if 
something  binds,  the  washers  will  turn 
against  each  other  so  that  nothing  is  dam- 
aged. But  under  normal  tuning^  they  turn  as 
a  unit  because  of  their  friction  contact  with 
the  shaft  and  with  each  other. 

The  same  idea  can  be  applied  in  adding  a 
scale  to  a  receiver  without  one.  The  2-B 
backs  up  the  spring  by  a  wide  margin  on  the 
shaft,  A  washer  against  the  panel,  a  spring, 
another  wide  washer,  and  then  a  felt  washer 
with  a  drop  of  oil  on  it  against  the  back  of 
the  scale  plate  will  allow  the  plate  to  turn 
freely  if  something  heavier  on  the  friction 
goes  between  the  plate  and  the  drive.  The 
gob  of  tape  or  a  metal  spacer  with  dry  felt 
washers  on  either  end  will  do  the  trick  here. 

For  a  professional  look,  paint  the  metal 
plate  holding  the  dial  black  or  to  match  or 
contrast  with  the  receiver  panel  and  knob. 
To  impress  your  friends  with  your  home 
brew  ability  and  with  the  fact  that  you  are 
one  up  on  them  with  the  same  old  gear, 
leave  it  a  shiny  aluminum  or  raw  bakeUte. 
The  entire  job  is  quite  simple  (about  two 
hours  work),  but  it  gives  the  impression  of 
immense  complexity  and  ingenuity.  And 
when  you  tune  in  your  caUbrator  note  and 
can  hear  it  for  a  couple  of  revolutions  of  the 


\  HQL€ 

TO  FIT     E>5S    SCREW 


"€3- 


LEMQTTH    AS  FtCaO 


'^ 


M 


If? 


■  o 


^>- 


-e 


_sr 


Ftg.  2.  Plates  needed  for  mountirrg  two- 
speed  dial/drive.  Adjust  dimensions  to  fit 
particular  receiver  being  modified. 
Note:  dimensions  of  slots  not  crttical,  but 
koep  slots  aligned  as  shown.  Reversal  of 
directions  allows  plate  holding  the  dial  to 
slip  more  easily  as  the  dial  is  rotated.  Lock- 
washers  are  essential  in  fastening  the  two 
plates  together, 

dial,    you    will    amaze   everyone,  includmg 
yourself. 

The  real  advance  is  in  operating  ease. 
With  a  slow  tuning  rate,  you  will  hear 
stations  that  you  previously  passed  over  as 
part  of  the  popping  Une  noise  and  QRN. 
Now  they  have  a  tone  that  rises  or  falls 
depending  on  which  sideband  you  are  tun- 
ing. "You  can't  work  'em  if  you  can't  hear 
*em",  is  an  old  saying,  and  we  can  add  that 
being  able  to  recognize  a  signal  is  half  the 
job  of  hearing  the  hard  ones. 

An  ultra-slow  tuning  rate  is  useless  with- 
out a  stable  receiver.  Some  receivers  drift 
faster  than  one  could  turn  the  knob  of  the 
new  drive  to  follow  them.  That  is  another 
place  the  straight-through  knob  comes  in 
handy.  But  stability  comes  first  on  the 
receiver  modification  priorities.  Once  you 
have  achieved  that  or  have  a  receiver  like  the 
2-Bj  which  remains  stable  even  as  it  grows 
old,  then  you  can  concentrate  on  tuning  rate 
and  cahb ration.  Here,  the  WRL  knob  and 
the  Jackson  Bros,  drive  really  help.  And  this 
is  the  point  where  I  came  in, 

.„.W4RNL 

*David  Middleton,  W7ZC/W5CA,  "Slowing  Down 
the  Tuning  Rate  on  the  Drake  2-B/*  73,  Septem- 
ber, 1965 J  p.  44- 


OCTOBER    1969 


45 


A,  R  McGee,  Jr,  K5LLI 
28 IS  Materhorn  Drive 
Dallas,  TX    75228 


Positive  Identification 


Calibrator  Harmonics 


The  availability  of  low-cost  high- 
frequency  transistors  and  integrated  circuits 
has  made  it  possible  to  build  inexpensively  a 
100  khz  crystal  calibrator  with  useable 
harmonics  extending  into  the  region  of  400 
to  500  rahz,*  This  means  that  you  will  have 
perhaps  4,000  or  so  crystal  controlled  signals 
available,  all  of  which  sound  exactly  alike 
when  tuned  in  on  a  receiver.  It  is  a  real 
problem,  therefore,  to  determine  which 
harmonic  of  1 00  khz  is  being  received  at  any 
given  time* 

The  usual  method  of  identification 

On  the  lower  frequencies,  when  using  a 
general  coverage  receiver,  you  can  tune  to 
WWV  at  some  known  frequency,  and  by 
carefully  tuning  away  you  can  count  the 
number  of  100  khz  harmonics  tuned 
through  until  you  reach  the  desired  fre- 
quency. For  example,  if  you  wish  to  locate 
7.0  mhz,  you  can  first  tune  to  WWV  at  5.0 
mhz,  then  tune  higher  in  frequency  until 
you  come  to  the  twentieth  100  khz 
harmonic  above  5,0  mhz^  This  wiU  be 
exactly  7.0  mhz.  Of  course,  you  must  be 
sure  of  which  WWV  signal  you  are  tuned  to, 
but  since  the  WWV  transmissions  are  spaced 
at  such  wide  intervals  (2,5  mhz  between  the 
2.5  and  5.0  mhz  signals,  and  5  mhz  between 
the  5.0  through  25.0  mhz  signals)  there  is 
little  likelihood  of  making  a  mistake,  even 
with  a  poorly  calibrated  receiver. 

Fossibility  of  error 

With  a  limited-coverage  receiver,  such  as 
the  ham-bands-only  type,  you  can  tune  to 
7-0  mhz  and  perhaps  you  will  hear  a  100  khz 
harmonic  at  this  dial  setting.  This  is 
probably  the  70th  harmonic  of  100  khz  at 


7.0  mhz,  but  it  could  also  be  the  69th  at  6.9 
pihz  or  the  71st  at  7-1  mhz,  and  the 
indication  would  stiU  be  exactly  the  same- 

At  higher  frequencies  even  a  receiver  with 
a  wide  tuning  range  will  have  the  same 
difficulty.  For  example,  say  you  build  a 
receiver  covering  the  range  of  100  mhz  to 
120  mhz.  A  grid-dip  meter  will  get  you 
somewhere  near  the  desired  range,  but  the 
100  khz  calibrator  will  be  useless  for 
accurate  calibration  because  you  will  be 
unable  to  positively  identify  any  of  the  200 
or  so  100  khz  harmonics  that  you  will  be 
able  to  hear. 

What  is  needed  is  some  means  of  giving 
each  harmonic  some  characteristic  that 
would  distinguish  it  from  all  of  the  other 
harmonics  generated  by  the  1 00  khz  calibra* 
tor. 

A  new  method  of  identification 

A  simple  way  to  do  this  would  be  to  use 
two  crystal  calibrators.  One  calibrator  would 
operate  at  exactly  100  khz,  while  the  other 
would  be  adjusted  to  operate  slightly  above 

100  KHZ 


1ST  XTAL 
OSC 

- 

HARMOMIC 

GEN 

— 

F 

P 

fiCVfi 

Fo 

FREQUENCY 
QQ\JHJi,R 

too  KHZ  i  Fi 

/• 

/ 

2  m  XTAL 
OSC 

- 

HARMONIC 
GEN 



AUDIO 
OUTPUT 

1 
1 

Fig.  1.  Block  diagram  of  proposed  method 
of  identifymg  lOOkhz  calibrator  harmonics, 
f=freqy@ncy  of  lOOkhz  harmonic  tuned  to. 
f1=frequency  difference  in  hertz  between 
first  and  second  oscillators,  fo-audio  output 
frequency  in  hertz. 


46 


73  MAGAZINE 


INTRODUCING  THE 


DELUXE 


MODEL  270 ...  5  BANDS ...  260  WATTS 


The  deluxe  Cygnet  is  a  complete  amateur  radio 
station  including  AC  and  DC  power  supply  and 
loudspeaker,  beautifully  integrated  into  one  pack- 
age. It  contains  all  the  features  required  for  home 
station  operation  with  enough  power  to  work  the 
world.  Yet  the  270  is  compact  and  light  enough 
to  make  an  ideartravelmg  companion  on  those 
business  or  vacation  trips  (second  only  to  the 
XYL,  of  course).  Incidentally,  a  carrying  case  for 
the  Cygnet  will  soon  be  available. 

For  temporary  mobile  installation,  either  in  your 
own  or  someone  else's  car,  Swan  will  soon  ofler 
an  installation  kit,  including  antenna,  which  will 
put  you  on  the  air  in  5  minutes  (no  holes).  Thus, 
you'll  be  able  to  operate  mobile  from  a  rental  car! 
For  permanent  mobile  installation,  your  Swan 
dealer  has  mounting  kits  and  5  band  antennas 
in  stock. 

For  those  who  feel  they  need  higher  power  to 
climb  above  the  QRM  tevel.  Swan  will  soon  an- 
nounce a  matching  1  KW  Cygnet  Linear.  It  will 
also  come  with  a  handle  just  in  case  you  decide 
to  take  its  25  pounds  along  on  a  trip.  With  this 
much  power  of  course,  it  works  only  on  AC. 


SPECIFICATIONS:  Power  Input:  260  watts  P.E.P.  tn  SSB 
voice  mode,  and  ISO  watts  in  CW  mode  •Frequency  Range: 
3,5-4.0  mc.  7.0-7.3  mc.  14.0-14.35  mc.  21,0-21.45  mc.  28.0- 
29  7  mc  •  C,F,  Networks:  Crystal  Lattice  Filter.  Same  as 
used  in  the  Swan  500  C  2 J  kc  band  width  at  6  db  down. 
4.6  kc  wtde  at  60  db  down.  Ultimate  rejection  exceeds 
lOOdb  9  Unwanted  sideband  suppressed.  50  db.  Carrier  sup* 
pressed  60  db.  3fd  order  distortion  down  approx,  30  db  # 
Audio  Response:  flat  wjthin  3  db  from  300  to  3000  cycles  m 
both  transmit  and  receive  modes  •  Pi  Antenna  coupler  for 
52  or  75  Ohm  coaxiaJ  cable  •  Grid  Block  CW  keying  with 
off-set  transmit  frequency  •  Solid  state  VFO  circuit  tem- 
perature and  voltage  stabilized  •  Receiver  sensitivity  better 
than  \z  microvolt  at  50  ohms  for  stgnal-plus-noise  to  noise 
'atio  of  10  db  #  100  kc  Crystar  Calibrator  and  dial-set  con- 
trol •  S-meler  for  receiver,  PA.  Cathode  meter  for  trans- 
mitter tuning  •  Improved  AGC  and  ALC  circuit.  Separate 
R,F.  and  A.F.  gain  controls  #  Sideband  selector  ©Provision 
for  plug  in  of  VOX  accessory,  as  well  as  headphones  and/or 
Cygnet  Linear  #  Tube  complement:  12BA6  VFO  amp.  12BE6 
trans,  mixer.  6GK6  driver.  6LQ6  pwr.  amp.,  6BZ6  rec.  R.F., 
12BE6  rec-  mixer,  T2BA6  1st  IF.  amp.,  12BA6  2nd  i.F.  amp., 
12AX7  prod,  det.  A  F.  amp..  6AQ5  A.F.  output,  12AX7  mfc, 
amp.,  6JH8  ba1!  mod.,  12AV6  AGC-ALC  amp.  Dimensionsr 
5V2  in.  high.  13  in.  wide,  11  in.  deep.  Weight:  24  pounds. 

Amateur  Net:    $525 
See  the  Swan  270  at  your  Swan  dealer 


ELECTRONICS 

OCfANSfDE.  CALIFORNIA  •  A  subsidiary  of  Cuhfc  Co^po^at^on 


ACCESSORIES 

Mobile  Mounting  Kit.  ........  . 

VX-2  Plug-in  VOX  Unit.  .  . 

5  Band  \  Model  45.  .  . 

Mobile  Antennas  J  Model  55.  .  . 


m       w      w      ^ 


$12 
35 
65 
95 


I 


or  below  100  khz.  Let's  see  what  would 
happen  if  the  second  oscillator  frequency 
were  made  100  khz  plus  10  hz,  or  100.01 
khz.  The  100  khz  and  the  100.01  khz  signals 
are  fed  simultaneously  into  a  receiver  that  is 
equipped  with  an  AM  detector.  If  the 
receiver  is  tuned  to  100  khz,  there  wiU  be 
audio  output  signal,  the  frequency  of  which 
is  equal  to  the  difference  in  the  two 
oscillator  frequencies*  In  this  case  the 
difference  is  1 0  hz. 

Now  we  will  tune  the  receiver  to  the 
second  calibrator  harmonic  at  200  khz.  The 
second  harmonic  of  the  100  khz  oscillator 
will  be  200  khz,  and  the  second  harmonic  of 
the  100.01  khz  oscillator  will  be  200.02  khz- 
The  difference  frequency  is  now  ,02  khz,  or 
20  hz,  which  is  the  audio  output  frequency. 
The  third  harmonics  of  the  calibrators  would 
be  300  khz  and  300.03  khz,  which  would 
give  an  audio  output  of  30  hz,  etc. 

As  we  go  up  in  frequency  the  spacing 
between  the  calibrator  harmonics  becomes 
greater  and  greater,  increasing  exactly  10  hz 
with  each  consecutive  harmonic.  This  could 
theoretically  continue  until  you  reached  an 
output  frequency  of  50  khz,  but  the  rf  and 
audio  bandwidths  of  most  receivers  would 
prevent  going  this  high. 

In  order  to  determine  which  harmonic  we 
are  tuned  to,  we  only  need  to  measure  the 
frequency  of  the  audio  output  tone  in  hertz 
and  divide  by  10.  Multiplying  this  answer  by 
1 00  khz  wiU  then  give  the  correct  frequency. 
After  determining  the  frequency,  you  can 
turn  off  the  oscillator  with  the  10  hz 
frequency  offset  and  zero  the  receiver  on  the 
exact  100  khz  harmonic  for  an  accurate 
calibration  point. 

Now  if  you  tune  a  limited-coverage 
receiver  to  7.0  mhz,  and  with  both  cahbrator 
oscillators  running  you  have  an  audio  output 
of  700  hz,  you  can  be  certain  that  you  are 
actually  tuned  to  7.0  mhz.  This  is  the  only 
frequency,  for  all  practical  purposes,  where 
you  would  have  a  700  hz  output  frequency, 
6.9  mhz  would  give  an  output  of  690  hz, 
while  7-1  mhz  would  give  an  output  of  710 
hz,  etc. 

Technical  details 

The  audio  output  frequency  would  have 
to  be  measured  very  accurately  -  at  least  to 
the  nearest  10  hz  or  whatever  100  khz 
frequency  offset  you  may  be  using,  A 
frequency  counter  would  probably  be 
required  to  get  accuracy  of  this  order.  This  is 
no  longer  the  hang  up  it  would  have  been  a 
few    years    ago.    The    introduction    of   in- 


expensive integrated  circuits  has  made  it 
possible  to  build  a  good  frequency  counter 
at  relatively  small  cost.^  ?  Some  of  the  older 
tube- type  counters  are  also  available  at 
surplus  outlets  at  reasonable  prices. 

For  our  purposes  the  counter  would  only 
need  to  be  capable  of  measuring  the  audio 
frequencies.  The  bandwidth  of  the  receiver 
would  be  the  limiting  factor  in  most  cases, 
and  the  100  khz  frequency  offset  would 
have  to  be  set  so  as  to  get  a  useable  output 
from  the  receiver  when  tuned  to  the  desired 
100  khz  harmonic.  For  example,  if  the 
receiver  bandwidth  is  10  khz^  with  a  10  hz 
offset  the  highest  measurable  100  khz 
harmonic  would  be  the  1000th,  or  100  mhz- 
With  a  5  hz  offset  you  could  measure  to  200 
mhz,  with  a  20  hz  offset  you  could  measure 
to  50  mhz,  etc. 

The  two  calibrator  oscillators  must  be 
accurately  adjusted  to  their  proper  fre- 
quencies. In  order  to  set  one  oscillator  to 
exactly  100  khz,  first  tune  the  receiver  to 
WWV  at  the  highest  receivable  frequency 
where  a  steady  signal  can  be  heard.  Wait 
until  the  tone  goes  off  (the  last  two  minutes 
of  each  five- minute  period)  and  adjust  the 
calibrator  frequency  for  zero  beat.  Watch 
the  receiver  S-meter.  When  you  are  close  to 
zero  beat,  the  meter  wiU  begin  to  move  back 
and  forth  at  a  rate  equal  to  thp  frequency 
difference.  Adjust  the  oscillator  trimmer 
carefully  until  the  meter  moves  very  slowly 
and  then  stops.  This  wiU  be  exactly  the  1 00 
khz  point. 

The  other  calibrator  can  be  offset  the 
correct  amount  from  100  khz  by  using  the 
counter  to  measure  the  beat  note  between  it 
and  WWV,  For  example,  with  a  10  hz  offset 
you  would  adjust  the  oscillator  for  a  1500 
hz  beat  note  with  WWV  at  15  mhz  (the 
150th  harmonic  of  100  khz),  or  a  2,000  hz 
beat  with  WWV  at  20  mhz,  etc. 

The  100  khz  calibrator  oscillators  must 
be  very  stable.  A  transistor  oscillator  built 
with  high  quality  parts  and  powered  by  a 
mercury  battery  would  probably  meet  the 
requirements.  A  simple  100  khz  transistor 
oscillator  developed  by  the  National  Bureau 
of  Standards  has  a  short-time  frequency 
variation  of  about  three  parts  in  10,000 
million,  and  a  long-interval  variation  of 
about  three  parts  in  1 000  million.* 

You  would  have  to  take  care  that  the 
oscillators  would  be  subjected  to  as  little 
change  in  temperature  as  possible.  Of  course, 
if  similar  parts  are  used  in  both  oscillators,  it 
is  probable  that  they  will  drift  at  approxi- 
mately the  same  rate  with  temperature  or 


48 


73  MAGAZINE 


+  cables 
^  connectors 

*  accessories 

*  applications  |^ 


(g(o)©S 


wsimmix 


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voltage  changes.  Thus  the  relative  fre- 
quencies of  the  oscillators  would  not  change, 
and  the  location  of  the  received  harmonics 
would  still  be  correctly  indicated. 

Receiver  stability  would  not  be  a  deter- 
mining factor  in  the  accuracy  of  this  system, 
as  long  as  the  caUbrator  harmonics  could  be 
held  withm  the  pass  band  long  enough  to 
enable  measurement  of  their  frequency 
difference. 

Since  this  output  frequency  is  the  result 
of  the  calibrator  harmonics  beating  against 
each  other  in  the  AM  detector,  a  slight  drift 
in  the  receiver  local  oscillator  will  not  cause 
a  change  in  the  output  frequency,  but  only  a 
decrease  in  its  amplitude- 

Considerable  thought  has  been  given  to 
the  ideas  expressed  here,  and  I  believe  that 
their  proper  application  would  result  in  a 
simple,  practical  method  of  positive  identi- 
fication of  any  individual  100  khz  harmonic 
heard  on  a  receiver.  I  have  not  tested  this 
system,  however,  mainly  because  I  do  not 
yet  have  a  frequency  count er<  1  don't  think 
any  great  problems  would  be  encountered, 
except  possibly  in  the  stability  of  the  caU- 
brator oscillators. 


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ON  EVERY  TYPE  OF  COAX 

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References:  (1)  Ashe,  "lUU  ktiz  1  liin-Line  Pulse 
Generator,"  73,  February,  1968,  p,  24.  (2)  JoneSj 
''An  Integrated  Circuit  Electronic  Counter j"  73, 
February,  1968,  p.  6,  (3)  Suding,  '*A  Cheap  and 
Easy  Frequency  Countefj"  73,  November,  1967,  p, 
6»  (4)  Kiver,  Transistors  in  Radio  and  Television ^ 
McGraw-HiU,  1956,  p-  141. 


Ham  Tips:  Save  That  Shielded  Braid 

Normally  discarded  shielded  braid  can 
be  used  as  both  a  soldering  aid  and  a  heat 
sink.  To  utilize  the  braid  as  a  soldering  aid, 
dip  the  tip  of  the  braid  into  some  rosin  flux. 
When  desoldering  components,  heat  them 
first  and  then  touch  the  braid  to  the 
terminal  The  mesh  on  the  braid  will  act  as  a 
sponge  and  soak  up  the  solder,  leaving  the 
terminal  clean  and  solder-free. 

When  soldering  to  heat-sensitive  compo- 
nents, use  the  braid  minus  the  flux  to 
conduct  excess  heat  away  from  the  compo- 
nent 

As  the  solder  fills  the  braid,  simply  clip 
off  the  solder  filled  portion  leaving  fresh 
braid  for  future  use. 

Happy  soldering! 

ElUott  S.  Kanter,  W9KXJ 


OCTOBER    1969 


49 


Adapting 


W,  B.  Cameron,  WA4UZM 
324  South  RiverhUls  Drive 
Temple  Terrace,  Florida    3361  7 


Transmitters   to   FM 


In  many  parts  of  the  country,  one  of  the 
most  popular  bands  today  is  two-meter  FM, 
Most  of  the  equipment  is  obsolete  com- 
mercial equipment  which  has  become  avail- 
able to  the  amateur  market  because  changes 
in  the  standards  necessitated  replacement  of 
the  old  wide-band  gear  with  newer  narrow 
band  equipment.  Some  new  FM  transceivers 
designed  especially  for  the  amateur  market 
are  beginning  to  appear,  but  they  are  in  the 
$300  range.  If  the  amateur  does  not  have 
access  to  obsolete  commercial  equipment  or 
the  inclination  to  adapt  it  to  amateur 
frequencies,  he  may  feel  cut  off  from  this 
interesting  mode  of  operation.  However,  it  is 
possible  to  get  on  the  air  experimentally  by 
adapting  existing  AM  equipment,  as  this 
article  will  show. 

The  first  thing  to  do  is  to  receive  some- 
body else's  signal.  If  you  have  a  two-meter 
converter,  you  can  do  a  passable  job  of 
receiving  strong  local  FM  signals  by  slope- 
tuning  an  AM  receiver,  or  using  an  FM 
adapter  which  is  available  for  some  receivers. 
If  you  are  receiving  narrow-band  FMj  the 
product  detector  in  a  sideband  receiver 
works  very  well. 

Once  you  have  heard  something  on  the 
aiij  the  next  problem  is  how  to  talk  back  to 
it.  If  you  have  an  existing  two-meter  AM 
transmitter,  the  likelihood  is  that  it  uses  8 
mhz  crystals-  The  easiest  way  to  adapt  this  is 
to  build  a  separate  FM  generator  which 
produces  a  signal  on  8  mhz  and  inject  it  at 
the  crystal  oscillator  stage, 

I  converted  one  such  transmitter  by 
removing  the  AM  modulator  stages,  and 
utilizing  the  sockets  which  were  there  to 
make  a  three  tube  FM  generator.  The  diagram 
and  parts  values  are  shown  in  Fig.  1-Two 
6SL7  tubes  and  one  6SG7  are  used.  These 
were  selected  simply  because  the  octal 
sockets  were  already  in  the  chassis.  More 
modem  equivalents  can  be  substituted  and 
only  very  slight  modifications  in  parts  values 
may  be  required  thereby. 

One  6SL7  serves  as  a  high  gain  voltage 


amplifier  for  a  high  impedence  microphone. 
There  is  nothing  very  special  about  this 
except  that  it  has  an  rf  trap  in  the  input, 
which  is  a  good  feature  to  build  into  any 
high  frequency  transmitter.  You  may  not 
need  it,  but  rf  has  a  nasty  way  of  getting 
into  the  grid  of  the  first  tube  without  it. 

The  other  6SL7  serves  as  a  Pierce  oscilla- 
tor and  a  PM  modulator.  You  will  note  that 
there  are  two  variable  capacitors  in  the 
crystal  oscillator  circuit-  The  25  pf  capacitor 
is  a  vernier  frequency  adjustment  for 
bringing  the  crystal  exactly  to  the  right  spot. 
The  100  pf  capacitor  controls  feedback-  The 
two  capacitors  interact  somewhat,  and  the 
feedback  capacitor  can  actually  be  replaced 
in  most  cases  with  a  small  fixed  mica  of  20 
to  50  pf,  but  if  you  put  the  variable  in  to 
begin  with,  you  have  the  advantage  of 
adjusting  for  optimum  output  even  with  a 
balky  crystal  This  may  prove  to  be 
important,  especially  if  you  have  to  doctor 
the  crystal  onto  frequency  yourself, 

Divide  the  desired  output  frequency  by 
36,  which  will  place  the  crystal  in  the  four 
megacycle  range  (146,940/36  =  408L666), 
You  can  order  a  crystal  with^  reasonable 
tolerance  from  a  number  of  the  firms  who 
specialize  in  regrinding  surplus  crystals.  The 
crystal  I  obtained  proved  finally  to  be 
slightly  too  high  in  frequency  to  net  with 
other  stations  on  the  air.  The  25  pf  con- 
denser was  not  sufficient  to  bring  it  all  the 
way  to  frequency,  so  I  used  one  of  the  old 
ham  tricks,  I  opened  the  crystal  holder  and 
carefully  drew  a  1/8  inch  circle  with  a  lead 
pencil  right  in  the  middle  of  one  side  of  the 
plate.  Upon  reassembly^  this  proved  to  have 
moved  the  crystal  just  enough  so  that  the 
APC  padder  would  puU  it  precisely  zero  beat 
with  other  stations  on  the  air,  I  found  a  20 
pf  fixed  capacitor  suitable  for  the  feedback 
circuit,  although  some  crystals  and  tubes 
might  require  as  much  as  100,  Obviously,  a 
crystal  oven  would  be  better  than  a  **raw" 

crystal,  if  it  is  available* 

The  second  half  of  this  6SL7  tube  is  a  PM 


50 


73  MAGAZINE 


4  MHZ   RANGE 

X  TAL 
\  .002 


OSC  MODULATOR  ' 

100  MICA  100  MICA  ,  50  MICA 


6SS7  g 


100  PF 


TO  RF 
OUTPUT 


0047  0047 

1 1(  *  w^HR 


8 


CRYSTAL    EXAMPLE 


40aJ  666    X    36  •    146  940 


to  WFD 

300  V 


vw 

47  IC 


-►     B    + 


Ffg,  1.  Simplified  8  mhz  FM  generator  and  crystal  substitute. 


modulator.  Do  not  bypass  the  22K  resistor 
in  the  cathode  as  this  degeneration  is  im- 
portant to  the  operation  of  this  stage,  I  will 
not  detail  how  this  particular  modulator 
works  except  to  note  that  it  produces  almost 
as  much  amplitude  modulation  as  phase 
modulation.  The  amplitude  modulation 
disappears  after  the  signal  is  passed  through 
a  number  of  saturated  stages,  which  is  one 
way  of  describing  the  hard  driven  multiplier 
stages  in  the  typical  transmitter  which  has  to 
multiply  a  fundamental  signal  36  times  to 
get  on  the  frequency.  You  can  check  with 
the  sensitive  rf  meter  at  various  stages  along 
the  line  to  observe  decrement  in  the  existing 
amplitude  modulation.  By  the  time  you  get 
to  the  final,  there  should  be  none  at  all. 

This  does  require  that  the  first  amplifier 
after  the  modulator  be  a  very  sensitive  high 
gain  stage.  I  found  a  6SG7  to  be  a  very 
suitable  tube  for  this  purpose.  Any  number 
of  miniature  tubes  w0  serve  as  well.  The 
only  thing  you  might  need  to  change  is  the 
screen  grid  dropping  resistor,  which  should 
be  adjusted  to  provide  the  proper  screen  grid 
voltage  as  indicated  in  tube  charts.  One 
further  question  remains  and  must  be  left 
open  to  experimentation  and  to  the  taste  of 
the  operator.  This  is  the  question  of  audio 
frequency  response.  PM  tends  to  sound 
tinny  and  some  roll  off  of  high  frequencies 
in  the  transmitter  or  receiver  is  required  to 
give  a  more  pleasing  sound.  This  can  be  most 
easily   accomplished   by  shunting  the  grids 


and /or  plates  of  the  6SL7  speech  stages  to 
ground  with  various  size  capacitors  until  you 
get  the  sound  you  want. 

Obviously,  this  simple  equipment  is  not 
likely  to  give  you  the  best  signal  on  the 
band,  but  then  you  haven't  invested  much  in 
it  either.  If  this  mode  of  operation  intrigues 
you  and  you  want  to  carry  experimentation 
further,  the  next  thing  I  would  recommend 
is  a  clipping  or  compressing  circuit  in  the 
speech  stages.  This  wiQ  help  maintain  a 
higher  average  deviation  while  restricting  the 
peak  deviation.  This  serves  the  same  basic 
purpose  as  ALC  in  a  side  band  transmitter  or 
clipping  and  compressing  in  an  AM 
transmitter,  namely  that  it  keeps  the 
apparent  percentage  of  modulation  at  the 
receiver  high  despite  a  wide  variation  in  the 
actual  level  of  sound  input  at  the  micro- 
phone. Again,  just  as  with  speech  treatment 
in  these  other  modes,  excessive  compression 
or  clipping  will  distort  the  sound  patterns 
enough  to  give  the  transmitter  a  very 
artificial  sound.  Taste  and  judgement  are 
required,  and  for  this,  you  need  a  good 
friend  on  the  air  who  can  give  you  a 
technically  competent  and  honest  report. 
This  may  be  the  hardest  part  of  the  whole 
operation  to  come  by,  but  the  FM  fraternity 
is  still  new  enough  to  include  a  great  many 
experimenters,  and  you  can  probably  find  a 
sympathetic  critic  in  your  area  if  you  look 
for  one. 

-  ,  ,  WA4UZM 


OCTOBER    1969 


51 


Rob  McKnIght  V/B2FHW 
Dave  Schmarder  WA2HNJ 
318  Dewey  Avenue 
Buffalo.  NY 


CB  Sets  on 


The  band  primarily  used  for  local  con- 
tacts  is  six  meters.  It  is  uncrowded  and 
transmitters  with  very  low  power  as  weU  as 
receivers  with  modest  selectivity  are  widely 
used.  Lack  of  a  simple  station  for  six, 
however,  keeps  many  otherwise  enthusiastic 
operators  away  from  this  band.  Having  to 
build  a  converter  for  the  station's  present 
receiver,  and  an  entirely  separate  transmitter 
for  six  is  not  very  appealing  to  many 
operators.  This  article  has  the  answer  to 
their  problem.  Its  subject  is  the  conversion 
of  the  ordinary,  everyday  CB  set  to  six- 
meter  operation.  Several  advantages  make  it 
worthwhile:  L  the  set  already  has  the  basic 
transmitter  and  receiver  circuits  and  thus  is 
easy  to  convert;  2.  its  transceiver  type  of 
operation  is  convenient  to  local  contacts; 
and  3,  it  would  make  an  ideal  local  vhf  net 
monitor  If  you  were  a  CB*er  turned  ham 
and  still  had  the  old  rig  hanging  around^  you 
would  have  the  added  bonus  of  not  having 
to  find  a  CB  set  to  convert  in  the  first  place. 

The  major  requirement  is  that  you  obtain 
a  CB  set  suitable  for  conversion.  By  suitable 
I  mean  that  it  should  be  a  tube  type  rig  and 
not  a  transistor  one.  Transistors  in  the  receiver 

work  at  27  mhz,  but  they  may  not  work  at 
50  mhz-  You  would  save  yourself  a  lot  of 
trouble  by  working  with  tubes.  As  far  as  test 
equipment  goes,  a  vtvm  and  a  grid  dip  meter 
are  very  helpful- 
Conversion 

The  receiver  section  of  the  transceiver  is 
converted  in  the  foUowing  manner: 

L  Tune  into  the  CB  band,  tune  up  the// 
cans,  and  get  the  set  working  satis  fact  orily* 

2,  Resonate  the  rf  and  mixer  coils  to  50 
rahz  with  the  grid  dip  meter-  Since  the 
oscillator    usually   runs    above    the    if  fre- 


quency, adjust  the  oscillator  to  its  proper 
frequency.  The  receiver  is  now  ready  to 
operate. 

3,  Tune  up  a  signal  on  six  meters.  In  place 
of  the  present  tuning  capacitor,  if  it  tunes 
too  great  a  range,  substitute  one  with  a 
smaller  capacitance  or  remove  several  plates 
from  the  one  in  the  set  to  give  less  frequency 
range.  This,  however,  may  not  be  desired,  as 
one  may  wish  to  receive,  for  example,  a 
MARS  frequency^  in  which  case  he  would 
rather  leave  the  original  tuning  capacitor 
untouched.  This  finishes  the  receiver 
conversion. 

The  transmitter  section  of  the  transceiver 
is  converted  as  follows: 

There  are  two  ways  to  convert  the  trans- 
mitter: 

1.  Leave   the   original   oscillator   in   the 

circuit  and  resonate  its  output  coil  to  50 
mhz.  Insert  a  5  0  mhz  overtone  crystal  in  the 
oscillator  and  you*re  finished.  Overtone 
crystals,  however ,  are  more  expensive  than  8 
mhz  ones,  and  are  usually  not  used  in 
today*s  six  meter  rigs.  On  the  other  hand, 
use  of  an  overtone  crystal  requires  one  less 
stage  in  the  completed  rig. 

2.  The  second  method  of  conversion  and 

probably  the  most  widely  used  is  the  use  of 
an  8  mhz  oscillator-tripler  stage  and  a 
doubler  stage.  Refer  to  the  circuit  diagram 
for  details.  Important:  Be  careful  not  to 
leave  out  any  bypass  capacitors  or  any  B+ 
decoupling  resistors,  otherwise  the  unit  may 
fail  to  oscillate,  or  a  stage  may  not  work 
properly.  An  extra  tube  is  required  in  this 
circuit,  that  being  the  doubler  stage,  which, 
as  indicated,  can  be  a  section  of  a  12AX7  or 
a  section  of  a  6U8-  In  addition  L4  should  be 
wound  inside  of  L3  for  good  coupUng.  The 


52 


73  MAGAZINE 


O5CILLAT0*?  TRIPLE!? 
eSHS  Oft  6A06 


aSMNz 


DOuetER 

l/Z  IZAX7  0R  (/2  6Ue 

50MH1 
^t ♦■ 


r2BY7 


50MH2 


.005 


Q-< 


SMHz 


Fig,  1.  Circuit  diagram  of  the  converter  transmitter  using  the  8  mhz  oscilfatortripler  and  the 
doubler  stage.  Coils  LI,  L3,  L4  were  afready  in  the  set.  L2  was  obtained  from  an  old  TV 
chassis.  This  circuit  diagram  may  seem  a  bit  incomplete,  but  since  every  CB  set  is  different, 
the  circuit  must  be  broad  enough  to  cover  all  models.  As  a  result,  some  experimentation  will 
be  necessary  to  determine  the  proper  coils  to  be  used. 


transmitter  conversion  is  now  complete. 
Tune  Up 

Procedure:  L  Hook  a  No.  47  pilot  lamp 
on  the  antenna  jack  or  terminals, 

2.  Set  each  coil  for  the  approximate 
frequency  indicated  on  the  circuit  diagra nu 

3.  Make  sure  the  oscillator  is  functioning 
properly.  This  can  be  determined  by  lis- 
tening to  the  signal  in  a  nearby  receiver.  If 
there  is  a  spot  switch  on  the  set  it  can  be 
used  to  listen  to  the  oscillator  in  the 
transceiver's  receiver, 

4.  Put  the  rf  probe  of  the  vtvm  on  the 
grid  of  the  doubler  stage,  and  tune  LI  for 
maximum  rf  indication  on  the  meter  (maxi- 
mum pointer  deflection).  If  an  rf  probe  is 
not  available,  put  one  end  of  a  1N34  or  an 
equivalent  diode  on  the  end  of  the  vtvm's  dc 
probe,  and  touch  the  free  end  of  the  diode 
to  the  circuit  to  be  measured, 

5.  Place  the  rf  probe  on  the  grid  of  the 
final,  and  tune  L2  for  maximum  rf  indica- 
tion, 

6.  Place  the  loading  capacitor  at  mini- 
mum capacitance,  and  tune  the  plate  tuning 
capacitor  for  maximum  brilliance  of  the  No, 
47  pilot  lamp  previously  hooked  up.  In- 
crease the  loading  by  increasing  the  capac- 
itance of  the  loading  capacitor,  and  then  dip 
the  current  using  the  plate  tuning  capacitor. 

7-  If  an  overtone  crystal  is  used  instead  of 
the  8  mhz  oscillator-tripler,  the  transmitter 
should  be  tuned  by  resonating  the  oscillator 
plate  coil  to  50  mhz.  The  rest  of  the  tuning 
is  done  as  described  above. 

You   now   have  a   complete   low  power 


station  for  six  meters-  All  that  remains  to  be 
done  is  to  hook  up  the  antenna  and  a  mike.  I 
might  add  that  there  is  really  no  need  to 
have  to  switch  the  beam  from  the  big  six 

meter  rig,  that  is  if  you  have  one;  the  set  got 
out  quite  well  on  a  simple  dipole  mounted 
on  a  stick  of  board.  The  total  cost  of 
converting  the  rig  was  nothing^  as  all  the 
necessary  extra  parts  were  available  from  the 
shack  junkbox.  So  if  you  want  to  have  some 
fun  on  the  band  which  is  becoming  more 
popular  every  day,  try  this  simple  con- 
version; you'll  be  glad  you  did! 

.  _  WB2FHW  &  WA2HNJ 

oscillatoi^iiitor 

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praciica  of  iti«  fesiling  of  moliij 
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#  atdi  in  bining  up  {Jf  (aitinf  HF 
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l»*dii«d  aluminum,  3.4  ■  1^3  ■  K2* 
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James  Research  company, dep't:  AR-M 

20  Witlits  Road,  Glen  Cove,  NY  11542 


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OCTOBER    1969 


53 


Proportional 


Cont  rol 


Crystal 


Robert  S.  Larkin,  W2CLL 

RFD  I  Box  28R 

Flanders,  New  Jersey  07836 


Oven 


When  the  ultimate  in  stability  is  required 
in  an  oscillator,  a  temperature  controlled  oven 
must  be  used.  Until  recently,  ovens  took  the 
form  of  a  box  surrounded  by  a  heating  ele- 
ment and  containing  a  thermostat.  When  the 
temperature  is  too  low  the  thermostat  closes, 
causing  the  heating  element  to  come  on.  Af- 
ter the  temperature  rises  to  the  thermostat 
switching  temperature  the  heater  goes  off,  al- 
lowing the  box  to  cool  down.  This  process 
continues  with  a  full  cycle  usually  taking  a 
few  seconds.  One  limitation  of  this  system  is 
having  the  heater  either  on  or  off  This 
means  that  at  all  times  there  is  either  too  lit- 
tle or  too  much  heat  being  applied.  The  re- 
sult is  a  cycling  of  the  box  temperature  as 
the  heater  goes  on  and  off. 

In  the  course  of  some  uhf  communica- 
tions experiments*  where  a  stable  frequency 
and  time  reference  were  required,  the  oven  des- 
cribed here  was  built.  This  oven  is  capable  of 
much  better  temperature  control  than  the  old 
thermostatic  type  of  oven.  Proportional  con- 
trol is  used  to  allow  the  correct  amount  of 
heat  to  be  applied.  Once  the  temperature  of 
the  oven  reaches  the  correct  temperature,  the 
heater  power  adjusts  to  some  level  between 


AC    FEEDSACtC 


THERMISTOR 


i-OrLTLJ! 

I  H£AT£R         I 


I  OVEf>i  I 

Fig.  1.    Simplified  diagram  of  oven  tempera- 
ture control. 

all  off  and  all  on  and  stays  there.  If  there  is 
a  change  in  the  temperature  outside  the  oven» 
the  heater  power  will  readjust  automatically 
to  keep  the  oven  temperature  constant.  This 
type  of  oven  is  used  in  almost  all  precision 
frequency  standards  in  commercial  use  today. 
Many  ideas  used  in  the  design  of  this  oven 
came  from  an  article  by  WX-  Smith  ^, 
An  interesting  aspect  to  this  type  of  oven 
is  its  relatively  low  cost.  With  any  kind  of 
junk  box  at  all,  this  proportional  oven  can  be 
built  for  less  than  the  cost  of  a  thermostatic 
type  crystal  oven- 


^^^^^2 


^3  I 


Vector  board  is  used  for  the  electronics. 
The  2  watt  heater  resistors  can  be  seen 
clamped  around  the  Minibox  oven.  When 
used,  the  oven  is  covered  by  insulating  ma- 
terial. 


54 


73   MAGAZINE 


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Circuit 

Operation  of  the  oven  control  is  best  un- 
derstood from  the  simplified  diagram*  The 
thermistor  is  a  temperature  sensitive  re- 
sistor^. Mechanically,  it  is  attached  to  the 
inside  of  the  oven  case.   Electrically,  a  bridge 


circuit  is  formed  so  when  the  resistance  of 
the  thermistor  is  equal  to  that  of  resistor  R, 
no  voltage  is  fed  back  to  the  input  of  the  ac 
amplifier.  When  the  thermistor  is  cooled,  its 
resistance  increases.  By  choosing  the  correct 
phasing  of  the  transformer  windings,  this  will 
cause  positive  feedback  around  the  ac  ampli- 


+  12  V    3  AMP   WAX, 


2N404 


CAPACITANCE    IN   UFO 


Fig,  2.  Diagram  of  proportional  oven  control   as  described  in  text. 

R1  Thermistor,     10000    at    25*^C,    GE    2D102, 

available  from  Newark  Elec,  500  N5,  Pulaski 
Rd,,  Chicago  IL,  part  no.  30F1 131,  Si. 60 

T1  Audio     Transformer     -    5200CT:22,OOOCT: 

600CT,     known  asW2EWL  SSB  transformer. 


\ 
I 
t 
I 

I 
r 

f 
I 

i_ 


NEATER 

C6)  tS  OHM 
2  WATT 


I 


OCTOBER    1969 


55 


The  thermistor  can  be  seen  mounted  on  the 
inside  of  the  Minibox  oven.  Paint  was  re- 
moved from  the  box  where  the  resistors  are 
mounted.  An  unpainted  box  would  be  pre- 
fersbfe. 

fier  creating  an  audio  oscillator.  The  voltage 

level  from  the  oscillator  is  converted  to  a  dc 
voltage  by  the  detector,  A  dc  amplifier  rai- 
ses the  power  level  to  a  maximum  of  about 
25  watts  to  drive  the  oven  heater.    As  the 

heater  warms  the  oven  and  the  thermistor, 
the  bridge  is  brought  back  to  balance  by  the 
lowering  of  the  thermistor  resistance-  If  the 
thermistor  resistance  is  lower  than  that  of  R, 
negative  feedback  occurs  around  the  ac  ampli' 
fier  and  no  oscillation  will  exist.  In  this  way, 
power  is  applied  to  the  heater  only  when  the 
temperature  of  the  oven  case  is  less  than  the 
desired  temperature. 

Between  the  point  of  no  oscillation  of  the 
ac  amplifier  and  full  cUpped  oscHlation,  there 
is  some  voltage  level  that  allows  the  heater  to 
supply  exactly  the  heat  lost  from  the  oven. 
Rather  amazingly^  this  feedback  airangement 
will  eventually  find  this  balance  point  and 
bring  the  heater  power  to  a  constant  level. 
Typically,  this  takes  about  30  minutes. 

The  actual  circuit  uses  two  2N167  transis- 
tors in  the  ac  amplifier,  and  two  2N404's 
and  a  2N174  in  the  dc  ampUfier*  These  par- 
ticular transistor  types  were  used  because 
they  were  readily  available*  Almost  any  simi- 
lar type  should  perform  satisfactorily. 

With  the  components  shown,  oscillation 
occurs  at  about  800  hz.  A  full  wave  detector 
provides  a  maximum  of  about  8  volts  to  the 
dc  amplifier.  This  amplifier  uses  three  emit- 
ter followers  for  unity  voltage  gain,  with  a 
current  gain  of  about  20,000.  The  heater  is 
built  from  six  15  ohm^  2  watt  carbon  resis- 
tors in  parallel. 

Construction 

The  layout  is  not  at  aU  critical.    A  heat 


sink  of  about  8  square  inches  area  was  used 
onthe2N174. 

A  standard  2^3/4"x2-l/8'*x  1-5/8"  Mini- 
box  (Bud  CU  3000  A)  forms  the  walls  of  the 
oven.  A  15  ohm  2  watt  resistor  is  fastened 
by  a  cable  clamp  on  each  of  the  six  sides.  To 
provide  good  thermal  contact,  the  side  of 
each  resistor  is  fUed  flat  to  a  width  of  about 
1/8".  Transistor  heat  sink  thermal  compound 
is  applied  between  the  resistor  and  the  Mini- 
box,  All  six  resistors  are  wired  in  parallel  to 
form  the  heater- 

■ 

In  order  to  minimize  tlie  time  required  for 
the  thermistor  to  sense  the  heater  tempera- 
ture, the  thermistor  is  mounted  inside  the  box 
behind  one  of  the  resistors.  This  gives  a  ther- 
mal lag  of  about  30  seconds  and  allows  a  rea- 
sonable warm-up  time  for  the  oven.  The 
thermistor  is  carefully  soldered  to  a  ground 
lug  that  is  then  electrically  insulated  from 
the  side  of  the  oven  by  a  mica  washer.  Again, 
heat  sink  compound  is  used  to  increase  the 
thermal  conductivity. 

Operation 

The  only  initia!  adjustment  required  is  the 


TIME  -  MINUTES 


Fig,  3,  Oven  warm-up  characteristics.  Tem- 
perature meastiremertts  were  made  at  the 
center  of  the  oven* 


phasing  of  Tl .  If  oscillation  does  not  occur, 
or  if  operation  is  very  erratic,  the  600  ohm 
winding  connections  should  be  reversed. 
Normal  operation  is  iQdicated  by  a  warm-up 
characteristic  similar  to  the  one  shown  in  the 
graph. 

The  oven  should  be  enclosed  in  an  insula- 
ted box.  This  reduces  both  the  heat  loss  and 
the  magnitude  of  harmful  transient  events 


56 


73  MAGAZINE 


FROM 


AMECO 


HEAVY  DUTY  SSB  POWER  TRIODE 

TYPE572B/T160L 

•  Ideally  suited  for  grounded  grid  linear  amplifier  service. 

•  Rugged  graphite  anode.       •  Compact  Envelope. 

•  Durable  bonded  thoriated  tungsten  filament. 

•  Relatively  low  operating  voltage  minimizes  power 
supply  cost. 

•  Zero  bias— no  bulky  auxiliary  power  supplies. 

•  May  be  used  in  instant-on,  no  warmup  amplifiers, 
for  home  brew  linears.  In  most  instances  the 
572B/T160L  directly  replaces  the  81  lA  providing 
greater  peak  power  capability  and  longer  life. 

MAXIMUM  ICAS  RATINGS  PER  TUBE 

DC  plate  voltage 2750  volts 

DC  plate  current 275  Ma. 

Plate  dissipation 160  watts 

Filament  power e^av®  4.0  Amps 

AMECO  DIVISION  OF  AEROTRON,  INC. 

U.  S.  HIGHWAY  1,  NORTH  •  P.O.  BOX  6527  •  RALEIGH,  N.  G.  27608 


such  as  cold  breezes.  A  1"  to  2"  layer  of 
foam  rubber  or  fiberglass  is  adequate  insula- 
tion around  the  oven. 

The  contents  of  the  oven  should  not  touch 
the  walls-  Components  inside  the  oven  are 
best  mounted  by  a  thermal  insulator  such  as 
foam  rubber. 

By  adjusting  R,  the  temperature  in  the 
oven  can  be  set  to  almost  any  temperature  a- 
bove  the  ambient.  The  maximum  tempera- 
ture attainable  is  limited  by  the  25  watts  de^ 
liverable  to  the  oven.  If  the  oven  is  well  in- 
sulated from  the  air  this  can  mean  tempera- 
tures over  100*  G  so  be  careful  or  you  may 
melt  your  new  precision  standard!  Even 
above  about  75*  C  some  components  may 
deteriorate.  The  oven  takes  about  30  minutes 
for  the  insides  to  warm  up  to  a  constant  tem- 
perature. As  shown  in  the  graph,  the  heater 
power  steadies  up  in  about  10  minutes  after 
having  considerable  overshoot. 

»,W2CLL 

Bibliography; 

1,  W,  L.  Smith,  "Miniature  Transistorized  Crystal 

Controlled  Precision  Oscillators/'  IRE  Transactions 

on  Instmmentation,  September  1960. 

2-   C-  K,  Klinart,  "The  Thermistor /'  73  Magazine, 

November  1968,  p.  78, 


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OOKiNC 

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OCTOBER   ISeS 


57 


■■■IP 


Donald  Mead  W2LT 
235  South  Irving  Street 
Ridgewood,  NJ  07450 


Crystal 


Phasing 


They  can  make  friends  enemies,  and 
enemies  friends^  by  philters/'  The  Anatomy 
of  Melancholy,  Burton,  1621. 

Yes,  even  back  in  the  1600s,  it  seems 
they  were  using  filters .  •  •  er,  phiJters,  that 
is  .  *  .*  to  perform  useful  feats  of  magic.  And 
what  better  legerdemain  can  be  found  in  the 
modern  communications  receiver  than  a 
crystal  philter ,  . .  filter,  I  mean. 


o 


[o] 


O  r.    O 


Fig,  1,     Front  view  of  the  unmodified  capa- 
citor, 

A  crystal  filter  is  useftil  in  improving 
receiver  selectivity  because  of  its  ability  to 
pass  one  frequency  while  attenuating  all 
others.  It  has  another  useful  attribute  as 
weU  -  its  ability  to  null  out  a  specific 
frequency  near  the  acceptance  frequency. 
The  use  of  a  phasing  control  permits  the  null 
frequency  to  be  varied  slightly  so  that  a 
near-by  interfering  signal  can  be  eliminated 
without  unpeaking  the  desired  signal 

Although  the  control  described  was  used 
in  the  **Second  Chance*'  circuit,*  it  can  be 
used  in  just  about  any  standard  if  crystal 
filter  circuit  with  untuned  grid.  The  phasing 
control,  which  is  simply  a  three-plate  van- 

*"A  Second  Chance  Crystal  FUter  foi  the 
BC-348",  73,  June,  1966. 


able  capacitor^  is  mounted  and  wired  in 
place  of  the  rotary  "crystal  on-off '  switch 
on  the  front  panel  of  the  BC-348.  The 
problem  is  —  try  to  find  a  small  variable  with 
an  insulated  rotor  shaft  in  any  of  the  parts 
catalogs!  After  much  looking^  we  became 
convinced  that  the  only  way  we  could  get 
what  we  needed  was  to  make  one.  The 
victim  was  a  small  AFC  variable  capacitor 
with  a  short  slotted  shaft  and  locknut.  These 
have  been  a  drug  on  the  surplus  market  for 
years  and  can  be  found  very  cheap.  Figs. 
1—4  show  details  of  the  modification. 
Surgery  is  performed  as  follows: 

a.  Remove  and  discard  the  locknut.  Next, 
with  a  knife  blade  or  slender  screwdriver^ 
spread  the  four  slotted  parts  of  the  shaft 
bushing  apart  and  bend  them  away  from  the 
shaft.  Flex  them  back  and  forth  until  they 
snap  off, 

b.  Remove  the  collar  from  the  tip  of  the 
shaft  by  filing  a  slot  in  the  collar.  It  is 
mounted  on  the  shaft  with  a  force  fit  and 
can  easily  be  pushed  off  once  it  has  been 
weakened  by  filing. 

c*  Position  The  shaft  so  that  the  plates  are 


Fig*  2.     Side  view  of  the  onmodified  capa- 
citor. 


58 


73  MAGAZINE 


disengaged.  Then  withdraw  the  rotor  assem- 
bly, taking  care  not  to  bend  the  three-legged 
flat  shaft  spring  (one  leg  is  the  rotor  con- 
nection termiiial  lug).  File  the  rough  surfaces 
of  the  shaft  bushing  on  the  front  of  the 
capacitor  until  the  bushing  presents  a 
smooth  bearing  surface.  Remove  all  but  the 
two  Stat  or  plates  and  the  one  rotor  plate 
nearest  the  ceramic  body  of  the  capacitor  by 
gently  bending  the  plates  back  and  forth 
until  the  soldered  joint  fractures.  File  or  clip 
off  the  excess  portion  of  the  stator  plate 
support  pins  and  the  rotor  shaft* 


Fig.  3.   Side  view  of  the  nnodifred  capacitor. 

d.  Prepare  an  insulating  sleeve  that  can  be 
forced  over  the  rotor  shaft  to  receive  the 
tuning  knob.  The  sleeve  must  be  1/4^'  in 
diameter  and  can  be  about  1/2"  in  length. 
We  used  a  plastic  test  prod  handle,  cut  to 
length,  that  merely  needed  enlargement  of 
the  bore  down  the  middle,  A  No,  21  driU 
makes  a  hole  that  fits  snugly  over  the  metal 
rotor  shaft.  The  tight  fit  is  important 
because  the  sleeve  must  be  forced  on  in  such 
a  way  that  the  rotor  contact  spring  is 
compressed  and  the  proper  spacing  between 
the  plates  is  maintained.  Incidentally,  the 
rotor  spring  may  be  flattened  a  bit  to  relieve 
some  of  the  pressure  it  exerts.  It  need  only 
make  good  electrical  contact  against  the 
shaft  shoulder  when  the  plates  are  properly 
spaced.  A  smaU  metal  washer  is  used 
between  the  bearing  end  of  the  plastic  sleeve 
and  the  filed  surface  of  the  bushing  to 
prevent  abrasion  of  the  sleeve.  To  assemble, 
place  the  rotor  contact  spring  in  position, 
insert  the  rotor  shaft  through  the  spring  and 
bushing,  add  the  metal  washer  over  the 
shaft,  and  force  the  plastic  sleeve  over  the 
rotor  shaft  until  the  plates  are  properly 
spaced,  noting  that  the  spring  is  sUghtly 
compressed  and  making  good  contact  with 
the  rotor  shaft.  This  completes  the  capacitor 
modification. 

The  phasing  capacitor  is  mounted  on  the 
panel  in  place  of  the  "crystal  on-off '  rotary 
switch-    The   original  knob   is  re-used   and 


FIq,    4.     Shaft  details;  (a)   before  modifica- 
tion, (b)  after  modification. 

covers  the  two  machine  screw  heads  holding 
the  capacitor  in  place.  A  small  piece  of  black 
plastic  tape  may  be  placed  on  the  back  of 
the  panel  to  cover  the  smaU  hole  which  the 
switch  anti-rotation  lug  occupied- 

By  bending  one  corner  of  the  rotor  plate, 
the  capacitor  will  short-circuit  itself  when 
the  plates  are  fully  meshed.  This  will  disable 
the  crystal  filter  and  provide  normal  low- 
selectivity  reception. 

One  word  of  caution  on  connecting  the 
phasing  capacitor  across  the  crystal  —  be 
sure  you  connect  the  grid  side  of  the  crystal 
to  the  stator*  We  inadvertently  connected  it 
the  other  way  first  and  heard  a  beat  note 
every  time  we  touched  the  metal  knob.  It 
turned  out  that  a  local  BC  station,  only  a 
khz  away  from  the  i/ frequency,  was  getting 
into  the  if  amplifier  through  the  shaft 
insulation  capacitance,  tiny  as  it  is!  Re- 
versing the  connections  cured  this. 

To  understand  how  the  filter  is  able  to 
perform  this  dual  role,  a  small  dose  of 
theory  may  be  helpfuL  First  of  all,  it  is 
important  to  accept  the  fact  that  a  quartz 
crystal  has  two  resonant  frequencies.  One  is 
the  series-resonant  frequency,  at  which  the 
crystal  offers  almost  zero  impedance;  the 
other,  about  1  khz  higher,  is  the  paraUel- 
resonant  frequency,  at  which  the  impedance 
is  very  high.  The  variation  of  impedance  as  a 
function  of  frequency  is  shown  in  Fig,  5,  At 
the  series-resonant  frequency,  the  crystal 
acts  like  a  series-connected  coil  and  capa- 
citor. L-C  combinations  Uke  this  are  useful 
as  wave-traps  to  short-ckcuit  undesired  fre- 


HIGH 


IMPEDANCE 


LOW 


1 


I 


Fig.   5.      The   variation  of   impedance  as  a 
function  of  frequency. 


OCTOBER    1969 


59 


quencies  in  the  output  circuit  of  a  trans- 
mitter or  in  the  input  circuit  of  a  receiver, 
for  example.  On  the  other  hand,  the  crystal 
also  looks  tike  a  parallel-connected  coil  and 
capacitor  at  a  slightly  higher  frequency.  The 
crystal  in  the  grid  circuit  of  a  conventional 
crystal  oscillator  stage  makes  use  of  this 
configuration.  Almost  everyone  is  familiar 
with  the  fact  that  the  frequency  of  a  crystal 
oscillator  can  be  lowered  slightly  by 
shunting  a  small  trimmer  capacitor  across 
the  crystal .  .  ,  a  point  to  keep  in  mind. 


^^ 


)l 

Fig.  6,    The  equivalent  "black  box"  electri- 
cal circuit. 

How  can  the  crystal  do  two  things  at 
once?  Let's  take  a  look  at  Fig,  6  which 
shows  the  equivalent  "black  box"  electrical 
circuit.  It  is  clear  that  Cx  and  Lx  are 
arranged  in  a  series  circuit.  However,  Ch, 
representing  the  capacitance  of  the  holder 
and  ^ wiring,  is  shunted  across  Cx  and  Lx. 


Lk 


Fig,  7.  The  pdratlef  resonant  combination. 

Redrawing  it^  as  shown  in  Fig.  7,  reveals  the 
parallel-resonant  combination.  Considering 
the  series-resonant  condition,  the  presence 
of  Ch  has  little  effect  on  the  resonant 
frequency;  all  it  does  is  to  act  as  an 
insignificant  by -pass  capacitor.  However,  in 
the    parallel-resonant    mode,    Ch    exerts    a 


XTAL 


MIXER 


6 


«FC 


Fig.  8.  Conventional  brfdga  circuit  with  the 
phasing  capacitor  adjusted  to  balance  out 
the  holder  capacity. 


definite  effect  on  frequency.  If  the  value  of 
Ch  is  increased  slightly,  the  parallel-resonant 
frequency  of  the  crystal  will  be  lowered 
slightly. 

In  the  conventional  if  bridge  filter  circuit, 
shown  in  Fig,  8,  the  phasing  capacitor,  Cp  is 
adjusted  to  balance  out  the  holder  capacity 
Ch  so  the  crystal  will  pass  only  frequencies 
at  which  it  is  series-resonant  Cp  can  be 
varied  slightly  either  way  from  the  balanced 
condition  to  indirectly  affect  the  parallel 
resonant  frequency  of  the  crystaL  Another 
way  of  doing  this,  especially  in  the  BC-348 
receiver,  is  to  connect  a  small  variable 
capacitor,  Ca,  directly  across  the  crystal  to 
permit  small  increments  of  the  holder  capa- 
city as  shown  in  Fig,  9,  If  trimmer  Cp  is  set 
to  balance  out  the  holder  capacity  plus,  let's 
say,  half  of  Ca,  then  any  change  in  Ca  will 

cause  Cp  to  have  a  surplus  or  deficiency  of 
capacity     as     far     as     balance     is     conr 

cerned  —  exactly   the  same  effect  as  if  Cp 

was  the  variable  control 


Mt)(£R 


RFC! 


Fig*  9.  A  small  variable  capacitor  is  con- 
nected directly  across  the  crystal  to  permit 
small  increments  of  the  holder  capacity. 

A  word  about  if  alignment  is  in  order. 
The  BC-348  selectivity  curve  with  the  filter 
out  is  as  wide  as  the  proverbial  bam  door. 
To  make  things  worse,  the  if  transformers 
are  slightly  overcoupled,  making  for  a 
double-humped  response  curve.  Originally^ 
we  felt  pangs  of  sympathy  for  the  designer 
who  had  to  accommodate  both  the  beacon 
band  and  the  hf  bands,  with  the  result  that 
the  if  landed  in  the  be  band.  But  to 
deliberately  broaden  the  selectivity  that 
much!  No  doubt  the  military  wanted  a 
receiver  that  stood  a  chance  of  getting  the 
message  through  when  tuned  roughly  to  a 
spot  frequency. 

The  rough  alignment  can  be  made  on 
background  noise.  With,  the  bfo  on  and  the 


60 


73  MAGAZINE 


crystal  filter  in,  advance  the  phasing  con- 
denser until  it  is  half  meshed.  Then  adjust 
the  trimmer  Cp  until  the  noise  has  a  tinny, 
rin^g  sound.  Then  peak  up  the  if  trans- 
formers (top  and  bottom)  for  the  loudest 
noise  with  this  characteristic  sound.  TMs 
completes  the  rough  adjustment 

For  the  final  if  alignment,  you  will  need  a 
stable  signal  generator,  preferably  one  that 
can  be  modulated.  We  found  that  the  vener- 
able BC-221-AK  is  perfect  for  the  job.  Also, 
you  will  need  an  ac  voltmeter  (say  0-5 V) 
that  can  be  bridged  across  the  audio  output 
as  a  tuning  indicator.  The  object  of  the 
exercise  is  to  find  the  exact  series  resonant 
frequency  of  the  crystal  After  this  has  been 
determined^  the  signal  generator  is  parked  on 
this  frequency,  and  the  final  adjustment  of 
all  z/ transformers  is  made. 

Couple  the  signal  generator  to  the  mixer 
grid  through  a  gimmick  condenser  made  by 
twisting  two  pieces  of  insulated  wire  to- 
gether so  they  overlap  for  about  one  or  two 
inches.  The  end  of  one  wire  can  be  stripped 
and  wrapped  around  pin  5  of  the  6SA7 
mixer  tube  which  is  then  replaced  in  its 
socket  Tune  the  signal  generator  slowly 
through  915  khz  (with  the  modulation  on 
and  the  bfo  off)  and  carefully  adjust  the 
frequency  for  a  maximum  on  the  audio 
output  meter.  If  you  have  hit  it  on  the  nose, 
the  phasing  control  can  be  varied  ±10 
degrees  rotation  without  appreciably 
affecting  the  output.  Peak  up  the  if  trans- 
formers. Repeat  the  procedure  to  double 
check  the  alignment  A  couple  of  hints:  use 
no  more  coupling  from  the  signal  generator 
than  is  needed  for  a  good  output  indication 
so  the  //  chain  won*t  be  overloaded;  also, 
short  the  antenna  binding  post  to  the  ground 
binding  post  to  prevent  the  reception  of 
spurious  signals  which  may  interfere  with 
the  desired  signal  from  the  generator. 

Before  disconnecting  the  alignment  set- 
up, try  testing  the  action  of  the  phasing 
control  in  nulling  out  a  weak  signal  near  the 
peak  frequency.  Detune  the  signal  generator 
about  1  khz  higher  than  the  alignment 
frequency.  Slowly  tune  the  phasing  control 
until  the  output  drops  drastically.  This 
adjustment  is  very  critical  and  takes  a  fine 
touch.  You  should  get  at  least  15  —  20  db 
attenuation  as  the  signal  drops  in  the  rejec- 


tion slot.  Try  other  offsets  from  the  align- 
ment frequency;  at  least  one  setting  should 
result  in  almost  infinite  rejection  as  the 
phasing  control  is  tuned  through  it* 

When  operating  the  receiver  in  the  "single- 
signal"  mode,  the  phasing  control  is  usu- 
ally set  so  audio  images  fall  in  the  re^ 
jection  slot,  That  is,  the  bfo  is  set  to  a 
desired  pitch  that  corresponds  with  the 
crystal  filter  peak  frequency;  Then,  the 
receiver  is  tuned  to  the  same  pitch  on  the 
other  side  of  zero  beat  The  phasing  control 
is  then  adjusted  to  eliminate  this  signal  (the 
audio  image).  In  this  way,  half  the  potential 
interfering  signals  are  automatically  elimi- 
nated whenever  the  desired  signal  is  tuned  in 
on  the  crystal  filter  peak. 


90e      9L0      9I£      914      916 


916      9S0     ^ZZ 


Fig.    10.     The  before  and  after  if  response 
curves. 

The  proof  of  the  pudding  is,  of  course,  in 

the  ability  of  the  receiver  to  dig  that  rare  DX 

out    of    the    pile-ups.    Using   a    homebrew 

converter  which  translates  10,  15  and  20  to 

the    80   meter   band    on    the    BC-348,    we 

worked  20  new  countries  in  two  weeks-  For 

the  more  scientifically  inclined  brethren,  the 

"before"  and  "after"  if  response  curves  are 

shown  in  Fig,  10,  Need  we  say  more? 

.  .  .  W2LT 


OCTOBER    1969 


61 


^ 


Grounded 


Ralph  S.  Yeandle,  W2IK 

P.  0.  Box  252 

Schoharie,  New  York    12157 


Filament  Chokes 


During  the  course  of  const  ruction  of  my 
linear  amplifier  employing  two  type  4-400  A 
tubes,  the  market  price  of  a  30  ampere 
filament  choke  was  suddenly  raised  from 
about  $9  to  around  $25,  Whether  this  was  due 
to  the  high  price  of  copper,  the  enamel  on 
the  wire,  or  because  a  beautiful  doll  needed 
a  new  diamond,  did  not  interest  me  one  iota. 
It  was  high  time  for  ingenuity  to  be  sum- 
moned forth. 

A  look  at  the  driving  impedance  of  those 
tubes  in  this  type  of  operation  indicated  a 
value  of  300  to  500  ohms  or  thereabouts, 
which  was  halved  for  two  tubes  in  parallel 
This  meant  that  the  choke  impedance  at  the 
lowest  frequency  to  be  used  should  have  a 
value  of,  say,  five  times  this  in  order  to 
maintain  a  low  r/loss  through  the  choke.  So 
we  are  then  talking  about  a  choke  imped- 
ance in  the  order  of  1000  ohms-  One  could 
wind  this  kind  of  a  choke  with  his  eyes 
closed  unless  he  considered  the  current 
requirement  of  the  tubes.  This  required  a 

very  heavy  wire,  size  No.  8  or  No, ,  1 0,  and 
even  then  a  good  fraction  of  a  volt  could  be 

lost  between  the  filament  transformer  and 
the  tubes.  When  a  coil  takes  on  these 
proportions,  there  must  be  a  better  way  than 
rolling  your  own. 

The  solution  was  easy.  Mount  the  trans- 
former on  insulators  at  least  Va"  thickness, 
thus  isolating  it  from  all  chassis  grounds. 
Then  connect  the  secondary  directly  to  the 
tubes  using  wire  of  sufficient  size  to  prevent 
any  appreciable  drop  in  voltage  to  the  tubes. 
If  you  find  that  the  transformer  has  an 
electrostatic  shield,  as  did  mine,  discormect 
it  and  let  it  float.  The  secondary  center  tap 
may  be  connected  through  a  choke  to 
ground  by  employing  one  of  those  small 
multiple-Pi  types,  but  if  you  are  particular 


about  getting  too  much  dc  resistance  in  this 
circuit,  and  about  wasting  a  good  high 
impedance  choke  where  it  is  not  needed, 
then  here  is  a  place  where  a  simply  con- 
structed device  can  be  used.  One  of  quite 
adequate  characteristics  can  be  made  on  a  1" 
diameter  form  about  3"  long,  wound  with 
about  No.  30  wire.  A  primary  choke  in  the 
110  volt  line  was  wound  in  bifUar  fashion 
with  No,  24  wire,  T*  diameter  and  about 
4¥i^  long.  The  heavy  capacitance  existing 
between  primary  and  secondary,  coming 
about  either  by  direct  coupUng  or  via  the 
core,  indicates  that  there  is  little  difference 
in  the  magnitude  of  the  rf  voltagje  on  either 
winding  and  therefore  the  same  amount  of 
choke  impedance  is  needed  for  each. 
Formex  insulated  wire  was  used  on  the 
bifilar  and  no  indication  of  breakdown 
between  adjacent  turns  has  been  evident  in 
the  three  years  of  use*  If  preferred,  two 
separate  line  chokes  may  be  used  in  the 
primary  in  which  case  each  can  be  physically 
smaller  than  the  bifilar,  A  .01  mfd  by-pass  is 
used  from  each  side  of  the  line  to  ground,  on 
the  line  side  only.  The  above  dimensions  are 
approximate  and  have  served  well  in  my 
amplifier  throughout  80  to  10  meters.  They 
were  duphcated  more  or  less  for  another 
amplifier  using  2  type  8 1 3  tubes.  Of  course  a 
high  quality  coil  form  may  be  used,  but  in 
this  case  the  circuit  impedance  is  sufficiently 
low  to  allow  an  old  broomstick,  hammer- 
handle,  or  a  dried  out  sapling  to  be 
used  -  even  at  1 0  meters. 

So  the  $25  with  which  I  almost  parted 
was  used  for  much  more  important  thin^. 
Come  to  think  of  it,  I  believe  that  I  bought 
an  anti-gravity  machine  from  a  door-to-door 
salesman, 

. .  W2IK 


62 


73  MAGAZINE 


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Capacitance  Substitution 

RF  Field  Strength 

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Thanks  to  transistors  and  prrnted  circuits  you  can 
hold-  this  complete  lab  in  one  hand.  Not  long  ago 
this  would  have  been  a  whole  shelf  full  of  test 
equipment.  455  khz  generator  for  aligning  if  s,  400 
hz  generator  for  audio  circuits.  Plus  a  normal  VOM 
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tuning  transmitters.   Everything  in  one  small  boxl 

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for  measuring  gain  of  each 
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stages.  Output  speaker 
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scope.  No  line  cord  since  it 
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n 


OCTOBER    1969 


63 


George  Wilson  WIOLP 
318  Fisher  Su 
Wa/po/e,  MA  02081 


uipment  Cabinets 

with  Style 


Most  experimenters  and  homebrew  equip- 
ment builders  settle  for  commercial  cabinets, 
boxes  and  chassis  to  house  their  electronic 
creations.  This  article  will  describe  a  method 
of  building  cabinets  that  are  simple  and 
stylish  and  that  can  be  built  in  a  wide  range 
of  sizes.  These  cabinets  have  minimum  cost 
and  yet  have  the  good  appearance  necessary 
to  make  your  radio  room  and  workshop 
look  highly  professional. 

The  solution  to  the  cabinet  problem  is  to 
build  wooden  cabinets  like  those  shown  in 
the  photographs.  Considerable  development 
has  gone  into  these  cabinets.  At  this  point  I 
feel  that  maximum  simplicity  has  been 
achieved  without  sacrificing  utility  and  style. 

The  accompanying  drawings  and  the  text 
that  follows  describes  a  **type"  of  cabinet 
rather  than  a  specific  cabinet.  If  this  type  of 
cabinet  is  attractive  to  you,  a  little  fore- 
thought is  in  order  so  that  you  may  adapt 
the  design  to  your  own  needs  and  to  the 
most  readily  obtained  materials.  The  width 
dimension  will  vary  depending  on  the  equip- 
ment that  is  to  be  housed.  On  the  other- 
hand,  perhaps  you  will  want  to  standardize 


T 

0 


ri 


l/Z 


.  I 

r1 


'  1 

1 L  ± 


r 


TOP    UtEW 
-  W 


T 


fSOMETRfC 
VIEW 


n 


± 


^ 


1~ 
1/4" 


^   . 


3/4" 


t/4" 


T 


2} 

3/4  15^41 1*1^4" 
RftNEL  STOPS 


FROWT   VIEW 


SIOC  VIEW 


SCREW  INTO 
PANEL  STOP 
(If  l«CE5SARYy 


PANEt  ATTACHMENT 
SCREWS 


REAR  COVER 
AS  APPROPRIATE 


SECTIONAL  VIEW 


on  the  height  and  depth  of  your  cabinets  so 
that  they  will  present  a  uniform  appearance. 
The  quarter-inch  plywood  recommended  for 
the  sides  of  the  cabinets  will  provide  plenty 
of  strength  for  even  relatively  large  cabinets. 
However,  if  you  have  a  source  of  another 
thickness  or  another  material,  it  can  proba- 
bly  be  used. 

Building  Suggestions 

The  quarter-inch  plywood  sides  and  top 
and  a  three-quarter-inch  pine  or  fir  base 
materials  appear  to  be  an  ideal  combination 
of  availability  and  usefulness.  It  is  suggested 
that  these  materials  be  cut  on  a  table  saw  if 
one  is  available-  A  table  saw  will  provide 
square,  relatively  smooth  edges  that  can  be 
assembled  without  further  furnishing.  So 
little  cutting  is  required  that  any  friend  who 
has  a  saw  should  be  glad  to  make  the  pieces 
for  you.  Cut  the  sides  and  top  from  a  single 


64 


73  MAGAZINE 


piece  that  has  been  cut  to  the  finished  depth 
dimension.  This  will  assure  that  the  top  and 
sides  are  aU  the  same  depth  and  that  they 
will  match  perfectly  when  assembled. 

The  panel  stops  in  the  upper  corners  may 
be  glued  to  the  top  of  the  sides  as  the  first 
assembly  step.  Use  white  glue  and  half-or 
three-quarter-inch  brads  to  fasten  the  various 
parts.  Next,  attach  the  sides  to  the  base  and^ 
last,  attach  the  top-  Use  the  white  glue 
generously,  but  wipe  any  excess  off  exposed 

surfaces  with  a  damp  rag.  When  the  glue  is 
dry  —  about  an  hour,  the  exposed  surfaces 
should  be  sanded  to  eliminate  any  ridges 
between  the  sides  and  the  top  and  to  provide 
a  smooth  surface  for  finishing*  A  belt  sander 
is  handy  for  this  operation,  but  hand  sanding 
is  easy  and  adequate. 


The  assembled  cabinet  should  be  sealed 
with  shellac  or  a  commercial  sealer.  It  can 
then  be  spray  painted  using  one  of  the 
quick-drying  enamels  or  lacquers  that  come 
in  spray  cans.  Build  up  three  or  four  coats. 
Each  individual  coat  should  consist  of  sev- 
eral light  sprays  with  special  attention  (re- 
sprayings)  being  given  to  any  spots  that 
tend  to  soak  up  the  paint.  Allow  at  least  a 
half-an-hour  between  coats  even  though  the 
label  will  claim  that  the  paint  ''dries  in 
minutes".  The  last  coat  should  provide  a 
high-gloss  finish  that  will  be  an  asset  to  any 
shelf  in  your  house. 

Nothing  has  been  said  about  choosing  the 
color  for  your  cabinets  and  very  little  will  be 
said.  However,  don't  overlook  the  possibility 
of  choosing  one  or  more  bright  colors  that 
wlQ  fit  with  your  decor.  I  use  a  "mix- 
and-match"  scheme.  In  the  workshop, 
cabinets  are  "color  coded'*.  Power  suppUes 
are  red  and  test  instruments  are  black.  The 
speaker  that  goes  with  the  commercial  re- 
ceiver in  the  radio  room  is  black  like  the 


negatives    for 

p.  c  t 


BIGELOW    ELECTRONICS 
BLUFFTON    OHIO  45817 


receiver. 

Panels  may  be  metal,  wood,  "hardboard 


»i 


or  a  plastic  such  as  Bakelite  depending  on 
the  needs  of  the  equipment  to  be  housed  in 
the  cabinet.  Hard  Masonite  with  a  couple  of 
coats  of  a  sealer  like  Firzite  makes  an 
attractive  looking  panel  that  is  easily  worked 
using  wood  tools. 

Panels  for  speaker  cabinets  can  be  made 
from  perforated  metal  or  with  openings  and 
grill  cloth  in  the  accepted  manner.  The  back 
of  a  cabinet  may  be  left  open;  closed  tightly 
with  wood  or  metal;  or  it  may  be  closed 
using  perforated  metal  or  screening. 
Openings  in  the  back  and  sides  may  be 
provided  for  cooling.  Heating  of  the  cabinet 
top  can  be  lessened  by  cementing  a  piece  of 
aluminum  foil  to  the  inside  of  the  top. 

The  front  panel  can  be  mounted  in  most 
cases  by  using  three-quarter-inch  round- 
head-wood screws  through  the  panel  into  the 
three-quarter-inch  base.  The  panel  stops  at 
the  top  will  prevent  the  panel  from  being 
pushed  in.  If  added  security  is  desired,  wood 
screws  can  be  used  in  the  upper  panel 
corners.  If  an  extra  long  cabinet  is  built,  it  is 
recommended  that  an  additional  panel  stop 
be  installed  on  the  inside  of  the  top  at  the 
center  of  the  cabinet- 
Uses 

Cabinets  of  the  sort  described  herein  may 
be  used  for  many  types  of  devices. 
Power  Supplies 
Timers 
Speakers 

Signal  Generators 
Bridges 
Clocks 
Chargers 
Meters 
Receivers 
Transmitters 
Standing  Wave  Meters 
Intercoms 

The  list  above  is  just  a  fraction  of  the  use? 
that  can  be  found-  These  cabinets  free  the 
equipment  designer  from  size  limitations 
and,  at  the  same  time,  provide  him  with  a 
source  of  easUy  made  cabinets  that  wil 
enhance  the  appearance  of  his  equipment. 

...WIOLF 


OCTOBER    1969 


65 


Richard  X  Zach  WB2AEB 
33  Pike  Place,  RFD'4 
Mahopac,  New  York  1 0541 


VHF  -  FM : 


Part 


Advantages    and    Practices 


When  you  operate,  what  do  you  want  in  a 
system?  You  may  say  reUability,  quality  of 
equipment,  as  well  as  ease  of  operation. 
Perhaps  you  have  as  insatiable  tliirst  to 
tinker  with  equipment  to  get  the  absolute 
best  performance,  VHF-FM  can  satisfy  all 
these  requirements  and  more. 

As  you  may  know,  VHF-FM  is  growing 
faster  than  any  other  mode.  Why  has  such  a 
relatively  new  concept  enjoyed  such  popu- 
larity? Perhaps  we  can  answer  this  by  asking 
still  another  question.  What  is  VHF-FM?  Of 
course,  you  could  say  that  you  FM  a  VHF 
transmitter.  But  VHF-FM  (or  just  ^TM" 
from  now  on)  is  also  an  enthely  different 
system  of  communications. 

About  75%  of  aU  FM  activity  is  operated 
from  the  mobile.  The  rigs  are  surplus  gear 
taken  out  of  commercial  service  (taxis, 
police  cars,  fire  trucks,  etc).  When  you 
purchase  these  rigs,  they  come  with  aU 
accessories  .  .  .  transmitter,  receiver^  power 
supply,  mike,  speaker,  control  head  and 
cables,  but  less  crystals  and  antenna.  They 
seldom  run  over  60  watts,  with  most  rigs 
running  30  watts  or  under.  Antenna 
polarization  is  always  vertical,  FM  deviation 
is  usually  wide-band  (±15  khz)  but  there  are 
a  few  scattered  narrow-band  outfits  (±5 
khz).  The  trend  today  is  toward  narrow- 
band operation,  though.  You  can  get  a 
complete  rig  for  as  little  as  $25,  but  the 
usual  price  runs  between  $40  and  $90  when 
obtained  from  a  dealer.  The  possibility  of 
obtaining  the  used  equipment  directly  from 
the  commercial  user  should  not  be  over* 
looked. 

As  noted,  just  about  all  FM  activity  is 
crystal  controlled   and  hence,  operates  on 


'channels.'*  Because  of  accepted  channels, 
repeater  stations  can  be  utilized.  Such 
repeater  stations,  usually  located  on  high 
ground  with  higher  power,  receive  signals  on 
one  frequency  and  simultaneously  retrans- 
mit the  received  signal  on  a  different 
frequency.  Going  through  a  repeat er,  you 
can  cover  a  50  mile  radius  using  just  a  one 
watt  walkie-talkie.  However,  in  speaking 
with  other  hams,  I  find  that  there  is  one  big 
misconception  about  FM,  It  seems  that  quite 
a  few  people  think  that  you  must  go  through 
a  repeater.  Quite  to  the  contrary.  As  a 
matter  of  fact,  m  southeastern  New  York^ 
most  FM  activity  is  "direct/'  without  the  aid 
of  a  repeater. 

Another  advantage  of  channelizing  is  that 
most  stations  can,  and  do  monitor.  When  an 
FM'er  gets  out  of  work,  on  goes  the  mobile 
rig-  When  he  gets  home,  on  goes  the  base 
station.  After  a  while,  you  know  when 
the  different  stations  are  monitoring.  You  are 
now  approaching  the  reliability  of  the  land- 
line  via  ham  radio. 

Emergency  communications  is  one  of 
FM's  strongest  points.  The  fact  that  all 
stations  are  always  on  frequency  and  FM 
receivers  are  not  susceptible  to  lightning  or 
ignition  noise  provides  for  an  extremely 
reliable  situation.  With  some  repeaters,  if  the 
commercial  power  fails,  an  emergency 
generator  automatically  kicks  in.  The  abun- 
dance of  mobile  and  portable  equipment  as 
well  as  the  fact  that  much  of  this  was 
designed  originally  for  emergency  use,  gives 
FM  the  upper  hand  in  most  any  emergency. 

Operating  procedure  on  channelized  FM 
is  somewhat  unique.  In  some  parts  of  the 


66 


73  MAGAZINE 


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country,  the  commercial  "lO-code"  is  used. 
This  does  provide  for  quicker  QSO's,  but 
this  aspect  of  operation  has  not  been  used  to 
any  extent  in  the  New  York  City  area  as  well 
as  many  others.  "CQ"  is  never  heard  on  FM^ 
since  there  is  just  no  need  for  it.  All  stations 
are  on  frequency,  so  no  long  call  is  needed. 

You  might  simply  say,  "This  is  WB2AEB 
monitoring  nine-four/'  and  that's  it.  If 
anybody  wants  to  gab,  theyll  answer.  Since 
the  channels  are  well  known,  when  referring 
to  them  you  simply  say  the  numbers  to  the 
riglit  of  the  decimal  point.  Thus  when  you 
refer  to  146.94  rahz  you  say  "nine-four." 
When  referring  to  52,525  mhz  you  say 
"five-two-five.** 

Even  where  six-meters  AM  may  reign  king, 
two-meters  is  often  where  the  FM  ham  stays. 
On  a  national  scale,  two-meters  is  also  the 
most  popular  channelized  FM  band.  146,94 
is  the  national  two-meter  frequency  with 
other  side  channels  such  as  146,76,  The 
national  6-meter  frequency  is  52.525  mhz, 

m 

There  is  also  a  national  ten-meter  frequency 

and  this  is  29.6  mhz.  There  are  about  300 

hams  on  this  frequency  and  more  are  joining 

every  day.  This  band  is  popular  because  the 

skip   comes  in   more  often  than  the  VHF 

bands.  To  get  on  ten-meters  FM,  you  simply 

tune  the  rig  down  to  29.6  mhz  instead  of 

52.525  mhz.  The  low-band  rigs  tune  from  25 

to  50  mhz  often  with  few  modifications. 

As  for  UHF^  the  %  meter  band  is  popular 

for    your    own    "secret"    repeater.    To    the 

FM'er,    six-meters    is    called     *iow-band," 

two-meters  is  called  ^*high-band,"  while  the 

%  meter  band    is   called    **450"  or  simply 

'^UHF," 

As  you  can  see,  FM  is  different. 


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I 


I 


OCTOBER    1969 


67 


1^ 


MMH 


Bring    Back 


Robert  L.  Greneli;  ex  WSRHR 
3926  Beech  Street 
Cincinnati,  Ohio  45227 


Multiplier 


Some  fifteen  or  sixteen  years  ago,  in 
another  amateur  publication  of  which 
Wayne  Green  was  editor  at  the  time,  the 
Q-Multiplier  was  introduced.  It  ijnmediately 
caught  on  big,  and  Heath  began  marketing  a 
kit  version  which  went  tJturough  several 
models  before  it  was  recently  dropped  from 
their  line.  Except  for  its  use  in  certain 
receivers  as  a  notch  filter,  it  has  now  just 
about  gone  out  of  style  with  the  ham 
fraternity. 

It*s  too  bad  that  this  has  happened^ 
because  a  Q-MultipHer  can  still  do  things  no 
other  circuit  can  for  the  same  price.  It  is 
capable  of  a  variety  of  functions  which 
would  otherwise  require  much  more  compli- 
cated and  critical  (and  expensive!)  circuitry- 
No  other  single  circuit  of  such  simplicity  and 
low  cost  offers  such  a  desirable  combination 
of  functions:  L  Single  signal  cw  selectivity; 
2.  Tunable  rejection  notch;  3,  Continuously 
variable  selectivity;  4.  Bandpass  tuning. 

How  It  Works 

If  all  this  sounds  good  to  you,  let's  take  a 
minute  to  examine  the  Q-Multiplier's  prin- 
ciples of  operation.  Normally,  more  or  less 
by  tradition,  the  Q-MultipUer  has  always 
been  set  up  to  work  with  a  455  khz  if. 
However,  with  proper  modifications  to  the 
tuned  circuit,  it  can  be  made  to  operate  well 
at  any  frequency  under  10  or  12  mhz. 

The  principle  .of  the  Q-Multiplier  is 
similar  to  a  suck-out  trap,  but  considerably 


more  sophisticated.  When  used  to  peak  a 
single  signal,  the  high-Q  tuned  circuit  in 
parallel  with  the  receiver's  first  if  stage  is 
regenerative  because  of  positive  feedbacks 
This  narrows  the  receiver  bandpass.  Effec- 
tively, the  triode  amphfies  the  high  Q  of  the 
tuned  circuit.  A  signal  passing  through  the  if 
at  the  tuned  circuit *s  resonant  frequency 
sees  a  very  high  impedance,  and  thus  passes 
by  the  Q-MultipUer  more  or  less  unaffected* 
A  signal  slightly  off  resonance,  however,  is 
sharply  attenuated,  since  it  sees  a  low 
impedance,  and  is  shunted  to  ground. 

In  the  notch  or  rejection  function,  nega- 
tive feedback  is  introduced  by  the  second 


.005 


^3^hr 


27K 


SIA 


RCUR 

1ST  if 


1  dFf 

2  BRQAD 
4,  fl EJECT 


4TK 


2tj3 


SELECTIVITY 


lOK 

NOTCH  DEPTH 


Fig.  1.  The  Greneli  Q-multiplier.  LI  &  L2 
can  be  either  the  Heath  coils,  if  you  rebuild, 
or  Miller  numbers  4414  and  4409  respec- 
tively. 


68 


73  MAGAZINE 


triode,  causing  the  impedance/frequency  re- 
lationship to  be  reverse d*  Thus,  a  signal  at 
the  resonant  frequency  sees  a  low  imped- 
ance, while  those  not  at  resonance  pass 
through  unaffected  by  the  high  impedance 
they  see.  The  sole  purpose  of  LI  is  to  tune 
out  the  capacitive  reactance  of  the  coaxial 
cable  used  to  connect  the  Q-Multiplier  to  the 
receiver  if. 

With  the  function  switch  in  the  sharp 
peak  position,  selectivity  down  to  about  200 
hz  is  available  for  CW  reception.  In  some 
installations,  it  may  be  possible  to  obtain 
1 00  hz  selectivity. 

How  to  Use  It 

The  peak  can  be  tuned  across  the  if 
passband  of  your  receiver  to  sort  out  a  maze 
of  signals  very  effectively.  Using  the  Q-Multi- 
pher  in  conjunction  with  a  selective  audio 
filter  is  just  about  the  ultimate  in  effective 
CW  reception.  You  really  shave  those  signals 
close!  1  omitted  the  broad  position  in  my 
installation,  since  the  selectivity  of  my 
75A-2  is  set  by  a  Collins  2,1  khz  filter;  but 
for  those  lacking  a  filter,  the  broad  position 
is  pretty  effecth^e  for  SSB  reception. 

In  extremely  crowded  band  conditions,  it 
is  possible  to  use  the  Q-MultipUer  to  separate 
SSB  signals.  With  the  selectivity  advanced  as 
far  as  necessary,  carefully  tune  across  the  if 
passband.  You'll  find  you  can  peak  up  the 
most  essential  voice  frequencies  of  the  signal 
you're  trying  to  haul  out  of  the  mess.  Under 
these  conditions,  the  audio  is  very  restricted, 
but  you  can  copy!  With  a  little  practice, 
you*ll  find  that  you're  able  to  slice  away 
SSB  QRM  just  as  effectively  as  you  can  in 
the  CW  mode. 

The  rejection  function  should  be  famJUar 
to  most  of  you.  It  works  just  like  a  T-notch 
filter  or  the  rejection  function  of  the  old 
style  crystal  filter.  Tuning  for  the  notch  is 
very  critical,  and  must  be  done  slowly.  It  is 
also  important  to  adjust  the  selectivity  con- 
trol for  the  deepest  possible  notch.  This  does 
not  correspond  to  the  setting  for  maximum 
selectivity,  but  falls  around  the  middle  of 
the  control's  range^  The  obvious  use  for  the 
notch  is  the  elimination  of  interfering 
heterodynes  and  adjacent  CW  signals.  How- 
ever, adjusted  for  a  slightly  broader  notch,  it 
wiU  do  a  fine  job  of  reducing  QRM  from 
adjacent  SSB  signals,  as  weU.  In  the  process, 


you*ll  probably  notch  a  good  chunk  out  of 
the  signal  you're  trying  to  copy,  but  -  again, 
with  practice  -  you'll  find  it  quite  effective. 

Building  One 

A  few  months  ago,  I  picked  up  one  of  the 
old  Heath  Q-MultipHers  from  a  local  ham, 
tore  it  down,  and  rebuilt  it  in  a  comer  of  my 
75A-2.  The  schematic  shows  the  final  cir- 
cuit, except  that  it  does  show  the  broad 
position,  which  I  omitted,  for  those  inter- 
ested. The  original  circuit  used  two 
pots  —  one  for  peak,  and  one  for  reject 
Since  the  two  functions  cannot  be  per- 
formed simultaneously,  I  used  only  one  pot 
on  the  panel,  and  put  the  pot  for  the  reject 
position  under  the  chassis,  since  it  only 
needs  to  be  set  one  time,  I  also  changed  the 
tuning  capacitor  from  a  100  pfd  unit  to  50 
pfd  to  obtain  better  bandspread  within  the 
passband.  The  100  pfd  variable  tuned  about 
5  khz  to  either  side  of  the  center  frequency. 
Those  who  will  be  using  the  broad  position 
may  want  to  retain  the  100  pfd  variable. 

The  Miller  coils  specified  will  work  nicely 
in  place  of  the  Heath  coils  I  used.  The  circuit 
layout  is  less  critical  than  you  might 
imagine,  and  point-to-point  wiring  is  OK, 
Before  making  the  connection  to  the  plate 
of  the  first  if  amp,  be  sure  your  receiver  is 
accurately  aligned.  With  the  Q-Multiplier  off, 
adjust  LI  for  maximum  signaL  Do  not 
re  peak  the  receiver  if,  or  you'll  degrade  the 
Q-Multiplier*s  performance. 

With  the  tuning  capacitor  at  mid-point 
and  the  Q-MultipIier  in  the  sharp  peak  func- 
tion, adjust  L2  for  maximum  signaL  Repeak 
LI  with  the  Q-Multiplier  off  and  L2  with  it 
peaking  about  3  or  4  times,  as  there  is  some 
interaction.  Now  check  for  the  performance 
of  the  rejection  function.  The  tuning  point 
of  maximum  rejection  wiQ  be  just  slightly 
different  than  that  for  maximum  peak 
because  of  the  capacity  of  the  second  triode 
switched  in  the  reject  function. 

That's  it*  You  should  be  ready  to  roU. 
You'U  find  the  Q-Multiplier  to  be  a  valuable 
addition  to  your  receiver.  1  hope  these  ideas 
wiU  stimulate  some  new  interest  in  this  most 
useful  and  versatile  gadget.  Since  Wayne 
Green  was  responsible  for  introducing  it,  it's 
most  fitting  that  he  should  have  a  hand  in 
re-introducing  it ! 

.  ,  .  W8RHR 


OCTOBER.  1969 


69 


Gerald  Price  VP2AC 
Care  of  Antigua  Star 
P,  O.  Box  114 
St,  John%  Antigua 
West  Indies 


Activation  in   VP2 


Both  in  the  American  phone  band  and 
the  DX  section,  hams  continue  to  say  the 
only  VP2s  that  we  have  not  worked  are 
Anguilla  and  the  British  Virgin  Islands. 
Meanwhile  several  hams  would  like  to  take 
along  their  rigs  while  holidaying  in  the 
Caribbean,  Because  of  this  I  am  writing  an 
account  of  my  recent  DXpedition  to  the 
islands. 

A  request  to  VP2MY  Frank,  the  man- 
aging director  of  Leeward  Islands  Air  Trans- 
port (LI AT) J  for  a  complimentary  flight  to 
the  islands  was  answered  with  an  immediate 
roger,  Frank  is  a  patron  of  the  Antigua 
Amateur  Radio  Club, 

My  next  move  was  then  to  get  a  license 
and  permission  from  the  St.  Kitts  Govern- 
ment to  operate  on  Anguilla  island,  Anguilla 
was  a  ward  island  of  St,  Kitts,  but  has  since 
seceded  in  June,  1967. 

A  telephone  call  from  my  home  QTH  in 
Antigua  to  the  telecommunication  officer  in 
St,  Kitts  resulted  in  my  learning  that  the 
officer  had  QRT  to  Canada  on  business  and 
that  I  should  write  to  the  Chief  Minister  of 
St-  Kitts  for  license  and  permission. 

A  hurried  letter  to  the  Chief  Minister  was 
answered  by  the  Minister  of  Communication 


1  §  ?  f  ¥3 


Jerry  VP2AC  making  first  stop  in  St.  Kitts 
to  get  government  permission  to  operate  on 
Anguilla  Island.  The  rig  here  is  an  HW-32 
with  a  Hustler  vertical* 


requesting  evidence  of  my  Brit^h  nationality 
before  consideration  of  the  license  could  be 
given. 

My  scheduled  time  of  departure  was  too 
short  for  correspondence,  therefore  it  was 
necessary  to  call  at  his  office  in  St.  Kitts; 
and  after  routine  inspections  of  my  Antigua 
license,  etc.,  I  paid  for  my  VP2K  license  and 
I  was  given  the  call  VP2KC* 

About  15  days  before  leaving  on  the 
DXpedition,  Hurricane  Inez  destroyed  my 
Hygain  vertical  which  was  slated  for  the  trip 
with  my  Hot  Water-32. 

An  immediate  request  to  New-Tronics 
Corporation  in  Ohio  for  a  Hustler  vertical 
brought  a  donation  of  a  4-BTV  Hustler 
which  I  received  five  days  after  the  request 
via  Amateur  Radio  Center  in  Miami,  Florida, 

On  St*  Kitts  island  it  was  necessary  to 
transfer  to  a  smaller  aircraft  which  would 

fly  to  Anguilla,  about  60  mUes  north.  This 
created  an  immediate  problem  —  the  6  foot 
by  1 14  inches  pipe  and  the  vertical  which  was 
telescoped  to  5  feet  8  inches  could  not  fit 
into  the  small  aircraft,  and  with  only  15 
minutes  before  QRT  time,  I  hurriedly 
bought  a  hacksaw  blade,  quickly  cut  off  18 
inches  of  the  pipe,  reduced  the  antenna  to 
about  5  feet  and  scrambled  into  the  six- 
seat  er. 

On  Anguilla  island,  I  booked  in  at  Lloyds 
Hotel,  the  most  elevated  location  in  The 
Valley  —  the  capital  or  chief  town.  The  hotel 
was  the  only  place  too  that  a  generator 
could  be  rented  at  a  moderate  price  -  there 
being  no  electricity  on  the  island, 

Anguilla  is  a  fascinating  island  in  the 
northerly  Leeward  group  of  the  Lesser 
Antilles  in  the  tropical  waters  of  the  eastern 
Caribbean-  It  is  a  flat  island  stretching 
eel-like   for  approximately   15   miles.  Prob- 


p 


70 


OCTOBER    1969 


»-*   I  - 


ill  .illlllllllll 


lirfTTfTtpiiMiiiiiiinn 
iiiiiiiilbumiiiuUtii 


Hustler  antenna  rs  being  cofinected  on  top 
of  the  hotel  room  in  Anguilla  Island,  From 
this  location  about  600  contacts  were  made, 
incfuding  WAC  and  65  countries. 

ably  named  L* Anguilla  by  the  French  who 
first  owned  the  island,  which  in  now  popu- 
lated by  about  7,000  people. 

The  antenna  was  ready  shortly  after  I 
arrived,  and  it  was  placed  on  the  roof  of  the 
hotel  From  here  the  sea  was  visible  from  all 
directions  way  out  to  the  horizon.  In  the 
distance  12  miles  away  was  the  French- 
Dutch  island  of  St.  Martin  silhoiietted  by  the 
sun. 

The  generator  was  set  into  motion, 
voltage  check—  118  volts  ac.  The  HW-32 
loaded  ok&y.  The  American  phone  band  was 
crowded  and  QRM  plus  plus.  I  gave  several 
CQ*s  which  resulted  in  no  reply. 

In  the  DX  section  the  first  station 
logged  was  VE3BWY  Ham  with  5x9  sigs 
both  ways.  Second  day  on  Anguilla  the  first 
stateside  station  logged  was  W2RSJ  and  then 
the  pile-up.  AU  districts  in  U.  S.  A.  were 
worked  except  the  7th  district  during  the 
five-day  stay  on  the  island. 

Several  VK's  were  worked  every  day,  in- 
cluding my  good  friend  VK4HR,  Harry,  who 

was  on  the  lookout  for  the  DXpedition;  and 


among  the  600  contacts  on  Anguilla  was  the 
ever-popular  PY2PS,  Eva. 

From  this  QTH  WAC  was  logged  and 
surprisingly  the  Russians  were  contacted 
long  after  1300  Zulu  unusual  at  this  time  in 
our  neck  of  the  woods. 

We  regret*  that  several  of  the  DL*s  were 
not  worked  when  they  were  coming  in  5  x  9 
plus  about  2000  Zulu,  but  the  generator 
stopped  and  it  took  sometime  before  we  got 
it  going  again.  Then  conditions  to  DL  land 
had  changed,  and  the  DX  section  was  prac- 
tically dead- 

But  the  American  Phone  Band  was  a 
bee-hive  of  activity.  Several  stations  were 
logged  before  I  found  out  that  I  was 
sandwiched  between  two  other  DXpeditions, 
VQ9AA  Don  on  Aldabra  and  FH8JF  Hosay 
on  Comoro  island  who  were  working  just 
about  30KC  apart 

Tortola  in  the  British  Virgin  Islands  was 
the  next  QTH  of  the  DXpedition,  but  before 
QRT  from  Anguilla  I  observed  that  the  local 
government  was  preparing  to  install  220-240 
volts  AC  in  The  Valley.  The  next  DXpedition 
to  Anguilla  may  be  much  more  comfortable 
for  the  operator. 

To  get  to  Tortola  from  Anguilla  it  was 
necessary  for  one  to  enter  St.  Thomas  in  the 
American  Virgin  Islands  if  one  wanted  to 
travel  by  air;  While  booking  for  St,  Thomas 
it  was  discovered  that  my  certificate  of 
vaccination  against  small  pox  was  missing, 
possibly  left  in  Antigua. 

A  quick  check  with  the  only  doctor  on 
the  island  and  I  was  revaccinated  and  given  a 
certificate.  In  St,  Thomas  swift  motor  vessels 
and  sea  planes  travel  to  Tortola,  and  to  cut 
down  traveling  expenses,  I  packed  the  equip- 
ment in  one  of  the  vessels,  and  I  was  happy  I 
did  because  I  made  a  good  study  of  the 
islands.  I  was  amazed  with  their  number  and 
proximity.  Here,  there  and  everywhere  were 
islands  —  Virgin  Gorda,  Anegada,  Jost  Van 
Dyke,  Salt  Island,  Peter  Island,  Cooper 
Island,  Norman  Island,  Marina  Cay,  Guana 
Island  and  many  other  islands  ranging  down 
to  mere  rocks  rising  from  the  blue  waters. 
We  sailed  through  Sir  Francis  Drake's  Chan- 
nel and  tied  up  to  the  pier  in  Road  Town 

Harbour. 

The  Tortola  customs  insisted  that  I  pay 
duty    on    my    equipment,    but   after  some 


« 


73  MAGAZINE 


71 


explanation,  I  was  allowed  to  pass  through 
free  of  duty,  pending  some  further  investiga- 
tion into  my  true  mission. 

On  Tortola  island,  the  Administrator,  the 
Telecommunication  Officer  and  the  Inspec- 
tor of  Police  gave  me  every  assistance  to  get 
up  the  station.  Thanks  to  to  the  Chief  of 
Police  in  Antigua,  Mr.  Edmund  Blaize,  who 
sent  letters  asking  for  assistance  and  reco- 
mendation  to  the  DXpedition.  Mr.  Blaize  is  a 
patron  of  the  Antigua  Amateur  Radio  Club. 

The  capital  Road  Town  is  a  true  valley 
completely  surrounded  by  high  mountains 
with  an  opening  from  the  sea.  To  my  mind 
this  location  was  not  ideal  for  a  DXpedi- 
tion  —  and  1  had  decided  to  QRT  to  Marina 
Cay  three  miles  away,  but  this  would  neces- 
sitate renting  another  generator  for  electric- 
ity -  and  enough  money  was  not  available 
for  this,  therefore  I  set  up  station  in  Road 
Town,  and  after  5  days  operating  here  560 
stations  was  logged. 

Tortola  is  the  largest  island  in  the  British 
Virgin  Islands  with  a  population  of  about 
8,000  people  who  have  a  strong  inclination 
to  be  Americans,  and  are  greatly  influenced 
by  their  neighbours,  the  American  islands  St. 
Thomas,  St,  Croix  and  St.  John. 

First  station  logged  from  Tortola  was 
YV2GT  sharply  followed  by  WICLX  and 
the  pile-up  bounced  in  over  the  mountains 
with  amazing  5x9,  Another  popular  YL 
logged  in  the  pile-up  was  WIRLQ  Grace  who 
was  worked  at  all  the  stops  as  well  as  from 
the  QTH  in  Antigua, 

Several  Africans  were  worked  every  day 
after  2000  Zulu-  The  SM's  were  constantly 
logged  and  several  HB9s  were  buried  in  the 
QRM.  My  good  friend  VP7NA  Harold  from 
the  Bahamas  was  logged  and  we  chewed  the 
rag  for  a  few  minutes.  All  the  Canadian 
districts  were  worked,  and  at  the  end  of  the 
Tortola  operation  WAC  was  again  logged  and 
65  countries  worked* 

My  QSL  Manager  WA4AYX  Pete  was 
constantly  monotoring  the  operations 
through  the  islands,  and  the  courtesy  of  the 
American  hams  was  indeed  commend- 
able —  while  my  QSL  Manager  and  I  were  in 
QSO,  they  were  all  QRX  until  he  was 
through. 

And  another  commendable  factor  of  the 
Stateside  hams  was  the  orderliness  in  which 


the  boys  came  in  when  caEed  in  districts- 
Being  transcieve  I  had  to  call  in  the  stations 
by  districts  because  of  the  tremendous 
pile-up. 

My  next  stop  was  the  island  of  Barbuda, 
and  I  had  first  to  return  to  Antigua.  Flights 
to  the  ward  island  40  miles  north  of  Antigua 
were  all  booked  until  one  week  later  Having 
only  25  more  days  of  vacation  I  decided  to 
move  immediately  and  boarded  a  fisMng 
vessel  for  Barbuda. 

I  was  the  sole  passenger  and  after  six 
hours'  sailing  we  anchored  m  the  placid 
lagoon  of  Codrington  Harbour. 

No  electricity  was  available  on  the  island 
and  therefore  I  set  up  station  at  the  PoHce 
Departmeht  with  the  kind  permission  of  the 
Chief  of  Police  in  Antigua, 

The  police  generator  delivered  230  volts 
ac  and  we  stepped  down  the  voltage  to  1 16 
volts  to  power  the  Hot  Water  -  32.  The 
police  officers,  some  were  my  schoolmates, 
helped  me  get  up  the  antenna.  We  went 
on  the  air  immediately  and  first  worked 
K2CWQ  who  is  believed  to  be  the  first  ham 
to  work  Barbuda;  there  being  no  record  of  a 
station  being  set  here  before. 

Station  K7TNE  Meg  was  worked  and  this 
was  the  first  and  only  station  logged  in  the 
Seventh  District  through  the  entire  DXpedi- 
tion*  After  5  days  of  spotty  operation,  480 
stations  were  logged  with  a  new  bird  FP8  AC 
on  St,  Pierre  Island,  At  this  moment  a  YV5 
broke  on  the  frequency  and  wanted  to  taJce 
over  operation,  but  I  would  have  none  of  it. 

Barbuda  is  a  very  flat  island  with  high- 
lands up  to  about  200  feet  in  the  northern 
section  of  the  62  square  mile  land.  It  is 
almost  all  of  coral  formation  with  a  very 
large  lagoon  on  the  western  side  which  leads 
to  the  main  and  only  village,  Codrington, 
where  1,200  people  live  like  one  big  family. 

It  is  one  of  the  few  islands  where  wfld 
deer  are  still  found,  and  the  only  island  in 
the  Caribbean  with  beaches  of  pinkish-white 
sands  stretching  for  more  than  1 5  miles. 

My  QSL  Manager  Pete  has  been  and  is 
still  handling  the  QSL  cards  for  Anguilla, 
Tortola,  and  Barbuda  DXpedition. 

My  next  DXpedition  is  being  planned  for 
Dominica  (VP2D),  St.  Lucia  (VP2L)  and  St. 
Martin  (FM7). 

. .  .  VP2AC 


72 


73   MAGAZINE 


Arnold  J.  Cain,  WB4FDQ 
375  Ruff  net  Road 
Melbourne,  Florida    S2901 


It  seems  now,  that  my  two-meter  antenna 
has  been  up  there  for  ten  years,  but  on 
checking  the  log,  I  find  it  has  only  been  a 

little  over  two.  Of  course^  it  may  only  seem 
that  way  because,  in  this  neck  of  the  woods, 
a  lot  of  hurricanes  and  high  wind  conditions 
have  tested  their  strength  on  this  rather  frail 
looking  piece  of  gear,  I  am  happy  to  report 
that  it's  still  doing  what  its  supposed  to,  in 
spite  of  them  ail! 

The  closest  we  have  come  to  disaster  was 
last  fall.  During  a  three- week  down-range 
trip  (I  was  working  at  Cape  Kennedy  as  a 
cameraman  at  that  time)  Melbourne  was 
sideswiped  by  a  small,  freak,  tornado*  On 
my  return  I  found  that  the  two-inch, 
thick- walled  aluminum  conduit  extension 
mast  that  supports  my  rotor  and  hf  antennas 
(and  which  is  guyed,  top  and  bottom)  at  the 
top  of  my  tower  was  bent  at  a  forty-five 
degree  angle  from  the  vertical,  leaving  the 
antennas  facing  the  ground  but  otherwise 
intact. 

This  small  twister  had  demolished  quite  a 
bit  of  valuable  property  in  our  town, 
including  a  beautiful  tri-band  array  at  the 
QTH  of  W4JHM,  only  a  hundred  and  fifty 
yards  west  of  us*  It  took  me  exactly 
thirty-five  minutes  to  saw  off  the  five-foot 
bent  portion  and  get  everything  back  up  in 
the  air.  So  much  for  the  rugged ness  of  this 
kite. 

As  you  will  see,  this  antenna,  even  if  you 
don't  scrounge  (as  1  do)  but  buy  all  of  the 
component  parts^  wiU  cost  almost  nothing. 
As  for  efficiency,  I'm  sure  there  are  antennas 
you  can  buy  or  build  that  wiQ  give  you  more 
gain,  greater  front-to-back  ratio,  etc. 
However,  for  simpUcity,  rugged  ness  ^  ease  of 
construction  and  compactness,  plus  broad 
handedness  and,  last  but  not  least,  cost,  you 
will  have  to  go  far  to  beat  this  one. 

One  more  word  on  efficiency.  I,  like  most 
of  our  breed,  do  not  have  access  to 
high-priced  lab  equipment,  but  I  do  have,  as 
you    do,  friends  and  fellow  hams.  K4JKX 


lives  about  fifteen  miles  away.  Using  a 
nineteen-inch  ground  plane  at  his  QTH,  he 
was  copying  me  at  less  than  one  half  S  unit 
on  his  SR42,  while  I  was  transmitting  on  a 
turnstile  at  about  fifty  feet  of  altitude.  After 
switching  to  my  little  CR  beam,  he  reported 
S  5-6,  a  gain  of  4^2-5  S  units.  If  this  isn't 
good  enough  performance  for  you,  you*ll 
have  to  experiment  with  one  of  your  own. 
So,  to  work! 

The  basic  materials  for  this  rig  are  a 
ten-foot  length  of  3/4  or  1-inch  aluminum  or 
steel  mast,  two  six-foot  and  one  eight-foot 
lengths  of  one-by-two-inch  cedar,  a  100-foot 
coil  of  aluminum  clothes  line,  (you  will  have 
about  25  feet  left  over)  40  inches  of  yi-inch 
aluminum  tubing,  and  assorted  bolts,  nuts 
and  insulating  material.  The  3/4-inch  or 
1-inch  aluminum  tube  will  be  the  mast  (I  put 
my  turnstile  for  local  ragchewing,  on  top). 


OCTOBER    1969 


73 


J 


t^imm 


tOUCAN  PUTYOOR 
TURN  STILE  HERE 


RCFLECTOR  ELEMENTS 

H^*  EA 

SPACED  MAX  OF  8' 


ALL  WOOD  PARTS 
1X2  CEDAR 


50  OHM 
COAX 


3/4''0R  I" ALUM. 


Fig.  1.   Corner  reflector  construction. 

Drill  holes  in  the  tubing  for  bolting  the 
58-irich  lengths  of  cedar,  approximately  ISVi 
inches  either  side  of  center  and  drill  the 
same  size  holes  (to  pass  i4  x  4"  bolts)  in  the 
584nch  cedar  strips  about  39y2'*  from  one 
tnd  of  each  strip  (the  ends  that  will  form  the 
apex).  Drill  holes,  for  force  fitting  the 
aiuminum  clothes  line  reflector  elements  in 
the  cedar  strips  every  8  inches,  measuring 
from  the  apex  or  corner  end  (you  may  put 
an  additional  element  at  the  apex  if  you 
wish  —  1  never  got  around  to  it).  Straighten 
the  clothes  Une  by  anchoring  one  end  to  a 
tree  or  other  firm  object  and  tugging  gently 
but  firmly  with  a  car  on  the  other  end.  You 
will  wind  up  with  a  nice,  straight  piece  of 
aluminum  wire  from  which  to  cut  your 
49-inch  reflector  elements.  Force  the  ele^ 
ments  into  the  holes  in  the  cedar  strips  until 
they  are  halfway  through.  I  put  a  drop  of 
weld  wood  glue  on  each  side  of  each  element 
and  have  never  touched  them  since. 

An  important  thing  to  remember  at  this 
point:  don't  put  the  reflector  elements  in 
until  you  have  layed  this  out  on  the  ground 
with  the  reflector  frame  strips  loosely  bolted 
to  the  mast,  because  you  will  have  to  driQ 
another  hole  in  the  mast  for  a  bolt  to 
support  the  boom.  The  boom  will  be  made 
in  two  pieces  so  that  the  director  elements 
will  be  in  Une  (horizontally)  with  the  driven 
element,  and  the  driven  element  in  line  with 


the  apex  of  the  comer  reflector.  To  have 
these  parts  line  up  accurately,  the  bolt  hole 
will  have  to  be  a  bit  below  the  center  and  it 
is  much  easier  to  do  this  with  the  whole 
assembly  laid  out  on  the  ground.  Once  you 
have  your  holes  drilled  and  are  sure  of  your 
alignment,  you  may  proceed  with  the 
assembling  which  wiQ  go  rather  quickly. 

For  final  assembly,  I  fastened  the  mast  up 
vertically  and  bolted  the  reflector  frame  to  it 
with  the  elements  glued  in  place  and  ran  a 
thin  bolt  through  the  back  end  of  the  boom 
and  the  reflector  frame*  I  put  the  drive 
element  on  last.  Make  sure  that  you  bolt  the 
wood  strips  all  on  the  same  side  of  the  mast. 
It  looks  awfully  furmy  the  other  way. 

Finally,  the  driven  element  —  I  must  say 
at  this  point  that  I  make  no  claims  for 
originality  concerning  any  portion  of  this 
rig  —  and  the  drive  element  is  no  exception. 
However,  in  self  defence,  I  have  found  that 
combining  these  various  components  in  this 
particular  way  may  be  a  bit  original.  The 
driven  element  has  been  written  up  before, 
under  different  titles.  Finding  it  to  be  all  it 
was  ever  claimed  to  be,  I  am  using  this  feed 
on  all  of  my  antennas.  Construction  is 
ample,  quite  weather  proof  and  gives  me  an 
SWR  of  1.5-1  across  most  of  the  band.  The 
whole  element  consists  of  a  half  wave  dipole 
of^  Vi  inch  aluminum  tubing  fed  by  a 
transformer  consisting  of  a  ^4  wave  piece  of 
RG8U  coax-shorted  (center  conductor  to 
outer  braid)  on  each  end  and  weU  taped, 
after  which  the  outer  insulation  is  cut  at  the 
center.  The  shield  braid  is  cut  at  the  center 
and  separated  by  about  1  inch  and  soldered 
to  about  a  four-foot  length  of  RG8U.  One 
side  to  the  braid  and  the  other  to  the  center 
conductor  of  the  feed  line.  All  joints  are 
taped  with  plastic  tape  to  weather  proof  and 
then  the  %  wave  piece  is  slipped  into  the  ^A 


COAK 


ORfVEN  ELEMENTS 
(/a"XJ9"ALUM  TUBES 

f 


t 


/ 


WOOD  SCREWS 
BOOM 


LUCITE  OR  OTHER 
tNSULATING  MATERIAL 


3 


t/4k  TRANSFORMEU 
tIPISlDE  DRIVE JMELEM.I 


COAX 


SOLDER  a  TAPE 
BRAID 


^^      RG: 

^^  'fn, 


RGS/U 


TRANSFORMER 


PIPE  CLAMPS 


SHIELD  8RA10  SOLDERED 
TO  CENT  COND 
TAPE  WELL  WtTH 

PLASTIC  tape;- 


BRAID 


CENTER 


1/4  ^ 

OR  )9  2*  AT  t45MC 


Fig,  2.    Detaifs  of  driven  element. 


74 


73  MAGAZINE 


wave  dipole  leaving  the  four-foot  section  of 
coax  for  feed  line. 

You  can  solder  your  coax  feed  directly 
without  the  four- foot  piece,  but  I  like  the 
convenience  of  a  short  length  for  testing  and 
pruning  purposes.  When  I  built  mine,  I  made 
each  driven  element  about  19  3/4  inches 
long  and  mounted  them  on  a  piece  of  scrap 
Va  inch  plexiglass.  Any  good  H.  F,  insulating 
material  will  do,  even  bakelite,  but  I  prefer 
the  high  poUsh  of  the  plastic  for  our  salt  and 
weather  conditions.  After  mounting  the 
driven  element,  I  prune  it  to  145mhz  using 

my  grid  dipper^  an  impedance  bridge,  and  a 
cheap  (95c)  tubing  cutter.  The  final  touch 
up  was  made  by  sUding  the  element  back 
and  forth  for  lowest  SWR  and  doing  the 
same  for  the  directors  for  highest  front  gain. 
The  sketches  should  make  everything  clear. 
That  about  does  it.  f'm  sure  that  if  you 
follow  the  pics  and  diagrams  reasonably 
closely,  you  will  wind  up  with  as  good  a 
signal  squirter  as  mine.  Good  hunting  on  *'2" 
and  "73"s. 

,  -  ,  WB4FDQ 

References 

"Infinite    Impedance    Match/'    7S,    March,    1963 

p.  20. 

J  965  ARRL  VHF  Manual,  pp.  208  and  225,  Figs. 

9-31. 


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OCTOBER    1969 


75 


^ 


Th 


e 


ARRL 


A.  David  Middelton  W7ZC 

Box  303 

Springdale,  UT  84767 


and  Amateur  Radio 


The  Anniiul  tnecting  of  ilic  ARRL  Board  was 
held  in  New  Orleans  on  May  2^  1969.  following 
several  days  of  informal  gatherings,  commiltce 
meetings  and  socializing, 

A  serious  attempt  was  made  in  the  early  *50s  to 
iiold  every  other  Annual  meeting  in  a  place  away 
from  tlie  sliadovvs  of  the  Ivorv  Tower  in  the 
Hartford  area.  Denver  '54  and  Montreal  ^65  are 
two  locales  of  this  meeting  of  the  Board  and  tlie 
no  entourage.  Tliere  may  liavc  been  other  travels 
for  this  important  (to  amateur  radio)  affair  where 
tlie  fate  of  AR  may  be  decided  or  at  least 
influenced.  However,  most  such  meetings  arc  held 
jiear  UO- 

Present  in  New  Orleans  were  fifteen  directors 
and  one  vice  director  acting  for  his  ailing  director. 
Also  present:  a  clutch  of  VPs;  the  General  Mana- 
ger-Secretary, the  Treasurer  and  four  vice  directors 
(who  did  not  get  their  expenses  paid  by  ARRL) 
and  a  bevy  of  HQ  personnel.  Missing  from  the 
roster  was  ARRL's  Public  Relations  Counsel  (Item 
101  of  the  1966  minutes  requests  that  a  study  be 
made  of  retaining  PR  counsel  to  attend  all  Board 
and  Executive  Committee  nieetingsK  Also  missing 
-any  representative  of  HQ/s  technical  staff* 

In  reporting  tlie  activities  of  this  meeting, 
material  has  been  placed  in  associated  areas,  each 
listed  in  a  tentative  '"order  of  importance''  related 
to  the  present  and  future  of  both  AR  and  ARRL- 
References  are  made  by  Item  number  and  are  not 
in  the  order  found  in  tlie  mineoed  minutes 
prepared  and  dislributed  by  the  Secretary.  Cate- 
gory headings  were  selected  by  this  reporter. 

Public  Relations-A  motion  (Item  12)  passed 
(11-4)  that  a  study  of,  and  recommendations  be 
made  for,  a  form  of  Field  Organization  which  will 
provide  contact  between  HQ  and  those  members 
whose  Interests  do  not  presently  coincide  with  the 
interests  of  the  Communications  Dept, 

What  ever  became  of  the  request  for  a  field 
Organization  setup -made  by  a  previous  Board  a 
few  years  ago?  Such  a  1".  0.  is  long  over  due  and 
badlv  needed  to  brins  ARRL  to  the  field! 

After  extended  discussion,  during  which  it  was 
almost  tabled,  Item  39  requests  (13-3)  that  a 
suitable  publication  be  written  by  ARRL  (after 
consultation  with  reading  specialists)  directed  at 
the  12-16  year  old  group. 

The  idea  is  commendable.  The  negative  votes 
are  inexcusable. 

A  unanimous  aftlrmative  vote  (Item  41)  in- 
stnicted  the  General  Manager  to  take  steps  leading 
to  the  addition  of  an  'Introduction  to  Amateur 
Radio''  course  to  high  school  and  adult  education 
classes, 

TIris  too  is  an  excellent  idea,  but  it  will  require 
heavy  follow-up. 

A  unanimous  vote  f  after  discussion -Item  44) 
instructed    the   General    Manager   to  periodically 


publish  m  CJST  information  on  ARRL\  structure, 
including  direciors  and  SCMs,  and  to  include  a 
glossary  of  ham  terminology, 

TMs  will  be  excellent  PR  and  should  enhance 
relations  between  ARRL  and  the  AR  bod  v.  All  too 
few  licenses  know  what  ARRL  is  all  about  and 
many  care  lessl  Such  indifference  does  not  always 
involve  personalities  but  is  often  related  to  ignor- 
ance of  basic  ARRL  concepts,  aims  and  goals.  With 
new  blood  coming  into  AR,  and  with  the  ever 
expanding  fields  of  endeavor  in  A R,  ARRL  should 
do  a  better  selling  job  of  itself. 

According  to  Item  60,  a  unanimous  vote 
requested  the  General  Manager  to  have  the  PR 
Counsel  prepare  material  for  distribution  to  pro- 
spective members  that  will  convey  the  tangible 
value  of  ARRL  affiliation  to  the  individual. 

This  idea,  together  with  that  immediately  pre- 
ceding it,  may  make  ARRL  membership  more 
meaningful  to  amateurs,  litis  PR  work  is  in  the 
ri*iht  direction  since  HO  has  failed  to  do  its  iob  on 
this-  Follow-up  is  necessary,  if  it  is  to  succeed. 

Item  81  states  that  W4GSX  will  be  presented 
with  ARRL*s  1969  Technical  Merit  Award  for  his 
analysis  of  typical  amateur  antennas  using  modern 
computer  techniques, 

\V4GSX's  work  will  be  awaited  impatiently  by 
many  who  have  been  looking  for  a  typical  antenna! 
Maybe  he  has  the  answers! 

Tills  reporter  (the  originator  of  ARRL's  Merit 
Award)  is  always  delighted  and  proud  to  see  tliis 
Award  made  b^  some  times  the  Committee  has 
passed  it  over  being  unable  (?)  to  find  anyone 
worUiy  of  the  Award.  It  should  be  noted  tiiat  the 
original  motion  creating  this  Merit  Award  included 
HQ  actions  to  properly  circulate  news  of  tiie 
Award  to  non-artiateur  media  in  order  to  obtain 
tlie  greafest  possible  PR  from  the  amateur's  work, 
which  resulted  in  Ms  Award.  Such  PR  has  not  been 
properly  done  and  much  of  the  value  in  the 
non-amateur  PR- world  has  been  lost. 

The  General  Manager  was  requested  (Item  87) 
to  "'continue  an  advertising  campaign  in  magazines 
wliich  might  be  read  by  individuals  who  are  likely 
to  have  an  interest  in  becoming  radio  amateurs,  in 
an  attempt  to  attract  more  individuals  into  the 
amateur  service*" 

Such  advertisements  should  be  of  great  value  to 
AR  and  to  ARRL.  The  word  ^'continue'*  implies 
that  such  advertising!  has  appeared.  This  reporter 
would   be   grateful  for  clippings  of  sucli  ARRL- 

placcd  ads  as  so  far  tliey  liave  escaped  his  notice 

with  one  exception- 
Defense  of  Amateur  Radio  Frequencies -The 

Dec.   31,    1968   ARRL  financial  report  indicates 

under  ''Reserves -for  defense  of  amateur  frequen- 

cies-S62,413.52." 

This  is  the  balance  of  a   SI 00,000   fund   tiir- 

nished    ARRL's   President    Hoover.  W6ZH,  some 


76 


73   MAGAZINE 


years  ago  and  which  had  become  depleted  witli  PR 
studies  and  other  expenses* 

Item  30  states  "on  motion  of  Mr.  Chapman, 
unanimously  voted  {Messers  Spencer  and  Thurston 
abstaining  [italics  supplied -ADM])  that,  in  view 
of  an  announcement  of  a  forthcoming  conference 
of  the  International  Teleconimunications  Union, 
the  Board  replenishes  the  $100,000  fund  for  the 
defense  of  amateur  frequencies." 

Althougii  little  has  been  heard  from  the  original 
SIOOK  or  the  nearly  $37K  spent  to  date,  this  fund 
could  become  a  vital  weapon  in  the  battle  to 
preserve  and  protect  our  frequencies  in  a  world 
that  seems  determined  to  take  over  all  low  and 
medium  high  amateur  bands  in  their  obnoxious 
spreading  of  tlieir  own  brand  of  propaganda. 

All  amateurs  should  be  keenly  interested  in 
what  ARRL  does  and  what  it  accomplishes  with 
this  SIOOK  fund.  Tliis  reporter  has  seen  Uttle  of 
the  results  except  the  Stanford  and  Waters  reports. 
The  latter,  at  leasts  was  worth  it!  That,  plus  some 
HQ  staff  junkets  to  foreign  lands  is  what  has  been 
seen  in  QST. 

ARRL  can  afford  to  spend  almost  its  entire 
resources  in  order  to  effect  suitable  safeguards  that 
will  help  preserve  and  retain  our  useage  of  all 
bands,  SIOOK,  if  properly  expended,  can  do  a  great 
deal  of  good  for  AR! 

ARRL  Membership- Item  42  orders  that  a 
postpaid  insert  inviting  membership  be  included  in 
selected  ARRL  publications  and  in  QST,  once  a 
year. 

The  necessity  for  such  a  Board  directive  escapes 
this  reporter.  HQ  should  have  been  doing  this  for 
years.  Such  a  motion,  or  the  need  for  it,  raises  the 
question -does  ARRL  HQ  really  want  ARRL  to 
have  more  members?  More  members --more  work- 
remember?  How  about  an  ARRL  membership 
contest-with  prizes?  This  idea  (Item  42)  should 
bring  results— if  it  is  followed  up, 

QST -A  motion  to  include  a  propagation 
column  in  QST  was  lost  when  it  was  tabled  (Item 

66)  by  a  vote  of  12-4. 

Some  will  argue  that  this  information  appears 
in  other  publications.  True,  and  some  have  wide 
circulation,  but  what  about  those  die-hards  who 
read  only* QST— and  need  this  information?  ARRL 
should  serve  its  membership  regardless  of  other 
publications. 

Item  68  requests  a  study  to  secure  more  rapid 
delivery  of  QST  in  6 -land,  KH6,  KL7  and  all  parts 
of  US  and  Canada  and  requests  that  the  results  of 
this  study  (by  the  General  Manager)  be  made  not 
later  than  the  next  Board  meeting. 

In  by-gone  days  one  could  tell  the  date  by  the 
arrival  of  QST,  This  reporter  believes  that  the  poor 
delivery  is  not  the  fault  of  the  QST  and  HQ  staff, 
and  offers  a  tliought  that  perhaps  the  postal 
employees  are  delaying  QST  by  reading  them 
before  delivery!  Could  be  potential  amateurs? 
Maybe!  If  they  were  ARRL  members  they  would 
get  their  own  copy  and  thus  perhaps  speed  up 
ours! 

ARRL-FCC  Matters-This  category  is  lengthy 
and  somewhat  confusing*  An  attempt  will  be  made 
to  shnplify  the  various  proposals  and  their  fate  at 
the  hands  of  the  Board. 

Item  13  requests  that  ARRL  petition  FCC  to 
permit  Conditionals  or  higher  in  the  KL7,  KH6, 
KP4  and  USA  insular  possessions  to  use  phone  on 
2L2  to  2L25  mhz»  Also^  that  ARRL  consult  with 
lARU  regarding  a  future  petition  to  FCC  to  permit 
phone  on  these  same  frequencies  by  Extras.  An 


amendment  withdrew  the  lARU  bit,  but  the 
amended  motion  was  defeated.  No  vote  count  was 
given. 

Item  14  would  petition  FCC  to  permit  Techs  to 
use  29.0-29.7  mhz.  This  was  amended  to  read 
29.5-29,7.  Vote- 14-1  with  the  Canadian  director 
abstaining  as  is  done  in  matters  pertaining  to  FCC, 

The  Planning  Committee  was  instructed  (Item 
19)  to  consider  the  feasibility  of  petitioning  FCC 

Expand  75-fone  to  3750-4000. 

Move  SD-Novice  to  3650-3700. 

Expand  40-fone  to  7150-7300. 

Move  40-Novice  to  7100-7150, 

Expand  20^fone  to  14175-14350, 

Move  15-Novice  to  21100-21200. 

This  Item  19  also  instructed  that  a  report  be 
made  by  the  next  Annual  Board  Meeting.  This 
motion  was  amended  to  establish  liaison  with 
lARU  to  evaluate  international  aspects  of  these 
possible  changes  and  to  report  by  the  next  Annual 
Board  Meeting.  The  amended  motion  was  passed. 
A  large  follow-up  tag,  please.  Miss  Blue! 

IF  Item  37  is  followed  tluough  and  IF  FCC  acts 
favorably,  devotees  of  the  art  of  EME,  MS  and 
other  valued  VHF/UHF  pursuits  will  be  granted 
higher  power. 

Note  the  IFs  in  that  statement.  High  power 
would  tremendously  aid  important  work  being 
done  by  pioneers  in  the  most  valuable  facet  of 
amateur  radio  yet  encountered  and  which  may  well 
become  our  only  area  of  activity  in  the  near  future. 

Item  53  requests  FCC  to  make  144-148  avail- 
able for  Technicians  instead  of  145-147.  ARRL 
win  so  petition  FCC, 

After  aU  somebody  has  to  use  those  highly 
valuable  4  megs!  It  is  assumed  the  Techs  would 
have  the  same  fone-cw  regs  as  others. 

If  FCC  agrees  with  the  motion  made  in  Item 
55,  potential  Extras  will  only  have  to  wait  one  year 
to  take  the  Extra  exam  instead  of  the  current  two 
years- 
Note  the  IF.  This  is  a  good  idea,  and  let's  hope 
FCC  likes  it.  Novices  and  Technicians  wiU  benefit 
if  the  intent  of  Item  55  is  OK'ed  by  FCC  and 
permission  is  granted  for  Techs  to  obtain  a  Novice 
license  without  surrendering  their  present  license 
and  waiting  one  year. 

An  excellent  proposal  will  be  made  to  FCC  that 
a  typewriter  (provided  by  the  amateur)  be  permit- 
ted in  copying  code  exams.  Item  73  (always  a  good 
number)  covers  this  but  its  originator,  the  well- 
known  contester  and  triple-A  CW  op»  W4KFC, 
overlooked  petitioning  FCC  to  permit  headphones 
over  the  ears  of  aspiring  examinees!  Any  trembling 
gun-shy  neophyte  will  welcome  a  mill  and  maybe, 
someday,  headphones  again^ 

Item  74  (which  was  passed)  requests  FCC  to 
assign  1x3  (preferred)  calls  to  Extras  who  request 
and  pay  the  fee,  such  calls  to  be  assigned  on  a 
random  basis. 

If  tliis  idea  gets  FCC*s  nod,  some  Extras  may 
get  desirable  calls.  Oh,  for  the  old  days  of 
call-swapping  and  initials  in  your  call  and  aU  that 
sort  of  thing,  sans  computers! 

MM  boys  will  be  pleased  if  ARRL's  support 
(Item  95)  leads  to  FCC*s  approval  of  MM  on  7  to 
7.1  mhz. 

AR  will  benefit  if  MM  is  so  allowed,  as 
MM-working  is  both  exciting  and  valuable  for 
contactees. 

RTTY  addicts  will  probably  rejoice  if  FCC 
grants  RTTY  operation  on  28-28.5  mhz  (Item  96) 


OCTOBER    1969 


77 


but  this  is  not  likely  to  be  favored  by  non-RTTY 
ten- meter  ops! 

This  same  Item  96  asks  FCC  to  move  *'CW 
only"  operation  from  1475-148  to  144-144,1,  It 
should  liave  been  there  long  ago.  ARRL  endorsed 
FCC*s  docket  18508  covering  tliis  item- 

Aithough  belatedly^  immigrants  to  our  shores 
will  be  permitted  ham  licenses  (after  filing  their 
fust  papers)  if  K7UGA*s  bill  S-1466  and  SJ  Res  27 
become  law:  ARRL  approves  this  (Item  97)  bill  as 
should  all  other  American  amateurs.  Reciprocity 
works  wonders! 

ARRL  HQ  Station  WIAW-HQ  was  ordered  by 
Item  15  to  establish  beacon  stations  on  one  or 
more  VHP  bands,  as  soon  as  practical,  to  operate 
at  regular  hours  and  on  a  published  schedule. 

This  recognition  by  the  Board  of  the  impor- 
tance of  VHP  in  the  ARRL  programj  altliough 
belated,  will  be  appreciated  by  all  amateurs  who 
realize  the  necessity  for  heavy  HQ  participation  in 
VHF  research  if  ARRL  is  to  keep  up  with  the  state 
of  the  art  and  advance  VHP/UHF;  Tliis  reporter 
firmly  requests  that  ARRL  put  an  EME  station  on 
the  air,  without  delay!  ARRL  HQ  should  lead  the 
way -not  foUow  the  crowd! 

Item  21  would  have  moved  ARRL*s  WlAW 
code  practice  and  bulletin  transmissions  out  of  the 
Extra  Class  portions  of  the  bands,  but  the  motion 
was  defeated* 

WlAW  should  be  operated  on  the  border  (in 
the  opinion  of  this  reporter  and  others)  between 
the  high  and  lower  class  segments,  where  practicaJ- 
ARRL's  argument  that  WlAW  is  not  a  frequency 
standard  station  may  be  true,  but  p^haps  the 
Comm.  Dept.  should  investigate  I969*type  high- 
stability  transmission  possibilities.  Few  stations  are 
equipped  with  25 -khz  markers  (even  if  they  have  a 
c^brator)  and  WlAW  could  help  them  know 
where  these  borders  lie.  ARRL  could  not  be  held 
responsible  for  a  legal  WWV-type  frequency  ac- 
curacy, but  being  near  the  border  (a  no-mans  land 
for  the  holders  of  the  lower  classes  of  Ucense) 
could  be  a  boon  for  all. 

Item  49  (debated  and  finaUy  adopted -vote 
14-2)  calls  for  WlAW  to  make  a  six  months  trial 
run  of  a  repeat  of  the  0230  GMT  scheduled  code 
practice  at  1300  or  so,  five  days  a  week. 

Why  would  any  director  (two  did)  vote  against 
such  an  idea?  Maybe  these  two  did  not  wish  to  rise 
at  1300  to  improve  theij  code. 

The  ARRL  Board  has  consistently  persisted  in 
using  an  irritating  practice  of  "referral  to  a 
committee  for  study/^  or  other  delaying  tactics 
when  faced  witli  a  sticky  problem  with  vvhicii  they 
did  not  wish  to  cope  or  make  a  firm  decision. 

Item  67  is  just  such  a  delaying  tactic  as  it 
authorizes  a  committee  to  work  with  the  OSCAR 
group  and  Foothills  College  in  California  to  investi- 
gate the  estabhshment  of  a  joint  ARRL/OSCAR 
station  at  OSCAR  HQ, 

Is  tliis  to  be  tlie  "west  coast  official  ARRL 
station"  mentioned  in  League  Lines,  June,  1969 
QST  or  is  this  to  be  the  $1500  ARRL  Space 
Station? 

The  Electronics  group  (plus  able  volunteers 
from  industry)  demonstrated  their  many  capabili- 
ties and  abilities  in  the  well-executed  OSCAR 
pro-ams  to  which  ARRL  gave  lip  service,  some 
QST  space,  and  the  ARRL  Technical  Merit  Award, 

This  reporter  believes  that  a  joint 
OSCAR/ARRL  station  would  be  Mke  the  infamous 
"horse-rabbit"  meatloaf,  made  of  equal  parts,  one 
horse  and  one  rabbit.  Name  the  horse  OSCAR, 


The  idea  of  a  west  coast  location  for  either  a 
WlAW-type  operation  or  a  Space  station  is  merit- 
orious and  should  implemented  without  further 
delay!  Yes,  Virginia,  there  IS  a  west  coast! 

If  this  is  the  HQ's  answer  to  the  1957  (Item  24) 
directive  allotting  $1500  for  an  ARRL  Space 
Station  J  then  why  wait  any  longer? 

The  director  of  the  Pacific  Division  (in  which 
OSCAR  HQ  is  located)  is  to  be  commended  for  his 
fortitude  and  success  in  getting  a  *'study'*  ordered. 
But,  why  a  study  on  a  west  coast  ARRL  station? 
There  has  been  a  dire  need  for  such  a  facility  for 
many  years  and  it  will  be  welcomed  by  all  who  live 
west  of  the  Hudson! 

The  Board  recognized  AMSAT  (see  June  QST) 
and  OSCAR  by  (Item  99)  appointing  liaison 
directors  to  these  timely  and  vital  programs. 

However  J  by  their  omission  of  N  AS  TAR  they 
indicated  eitlier  their  indifference  to  the  placing  of 
a  ham  repeater  on  the  Moon,  or  their  ignorance  of 
NASTAR,  or  both. 

$1500  for  an  ARRL  Space  Station?  Many 
VHFers  have  antennas  that  cost  that  much- 
ARRL's  stated  worth  (Dec,  31,  1968)  was 
$1,244,288.45!  Is  ARRL  reaUy  interested  in  VHF 
or  not? 

ARRL  and  VHF  Repeaters- the  modus  oper- 
andi of  the  Board  can  not  be  more  clearly 
demonstrated  than  in  the  progression  of  a  good 
idea  to  a  weak  one-as  shown  in  Items  20,  38,  51 
and  89. 

Item  20  (tabled)  comprehensive  reporting  of 
and  an  interest  in  VHF  repeater  operation  by  HQ 
personnel  and  in  QST  space.  Item  20  also  called  for 
a  section  of  the  ARRL  H-Book  to  cover  VHF 
repeaters  and  their  operations.  This  motion  was 
well  organized,  vitally  needed  by  those  who  get 
their  Icicks  form  this  newest  facet  of  ham  radio,  a 
phase  that  is  rapidly  growing  in  popularity  and 
usefulness. 

Item  38  (tabled  by  a  vote  of  ARRL^s  President, 
after  a  tie  vote  by  the  directors)  called  for  a 
separate  VHF  REPEATER  handbook  to  be  written 
and  published  by  ARRL. 

In  Item  51  the  director  who  made  the  proposal 
in  Item  20  (apparentiy  in  a  desperate  effort  to 
salvage  something  from  his  good  idea)  amended  his 
original  motion,  albeit  emasculated,  to  request 
QST  to  carry  news  of  VHF  repeater  activities  in  a 
principle  subsection  of  The  World  above  50  MC: 
This  amended  motion  was  then  passed. 

The  same  director  then  proposed  (Item  89)  that 
ARRL  include  a  section  on  VHF  repeaters  in  the 
1970  H-Bk-  This  motion  passed- 

Note  that  Item  89  calls  only  for  a  section  in  the 
70  H'Bk, 

Your  attention  Is  called  to  Items  20-38-51  and 
89  as  a  study  in  Board  procedure,  when  faced  with 
HQ  opposition  and  Board  indifference!  This  study 
should  be  entitled-'*how  to  have  a  good  idea 
ruined  without  really  trying!"  The  reporter  is  sure 
that  ardent  VHF  repeater  fans  will  have  less  than  a 
huzzah  for  the  Board  on  this  matter. 

Item  61  authorizes  the  General  Counsel  to  file 
comment  and  to  petition  FCC  to  impliment  the 
report  of  the  VHF  Advisor>'  committee  with 
consideration  given  the  status  of  various  related 
rule-making  procedures  now  pending  with  FCC. 

ARRL-RTTY  Matters-ARRL  approved  (Item 
17)  FCC's  Rm  132  (pending)  permitting  RTTY 
operation  at  60,  75  and  100  wpm.  Good  thinking! 

Director  A  flairs --Several  motions  were  made 
regarding  directors,  their  duties  and  other  matters. 


78 


73  MAGAZINE 


Item  11  called  for  procedure  of  impeachment  of 
any  office  holder  elected  pursuant  to  the  Articles 
of  Assoc,  the  By-laws  and  the  responsibilities  of 
his  office.  This  motion  passed.  Perhaps  we  may 
now  have  a  method  of  ridding  ARRL  offices  of 
incompetents, 

At  last  (Item  58)  ARRL  directors  (not  vice 
directors)  are  authorized  to  attend  ARRL  National 
conventions  with  expenses  incurred  chargeable  to 
authoiixed  division  aUotmen ts. 

It  might  be  noted  that  the  1969  ARRL 
National  Convention  was  scheduled  for  Iowa,  the 
home  state  of  ARRL's  president.  Any  connection 
purely  coincidentaL 

Why  has  it  taken  until  *69  to  get  such  a 
worthwhile  measure  passed?  Not  many  directors 
have  the  wherewithal  to  travel  on  their  own 
expense  and  few  can  arrange  "business  trips"  to 
permit  their  attendance  at  ARRL's  own  national 
event  This  motion  is  worthy  and  this  reporter 
trusts  that  all  directors  will  take  fuM  advantage  of 
it* 

Item  36  (which  passed)  is  of  extreme  impor- 
tance! It  is  also  highly  significant  of  what  may  be  a 
new  progressive  spirit  in  the  Board, 

A  Special  ARRL  Board  meeting  is  called  for 
Nov,  1,  1969  to  consider  or  act  upon  the  follow- 
ing- 

1.  Actions  pending  before  FCC. 

2p  Reports  and  studies  of  HQ  staff- 

3*  Amateur  band  occupancy, 

4.  Committee  recommendations. 

5.  Establishment  of  an  ARRL  Foundation, 

6.  Recommendations  of  Counsel  regarding 
amendments  to  provide  for  two  meetings  of  the 
Board  each  year. 

This  item  also  states  that  any  other  matters  to 
be  placed  on  the  agenda  may  be  added  up  to  and 
including  Oct.  22,  upon  concurrence  of  at  least 
nine  directors, 

Note  that  a  majority  must  concur  even  to  get 
an  item  on  the  agenda.  However,  the  agenda  is 
potentially  loaded! 

Item  36  also  urged  directors  to  arrive  at  the  site 
of  the  meeting  as  far  in  advance  as  possible  and 
reasonable  for  committee  and  informal  confer- 
ences. 

This  is  SOP,  allowing  several  days  for  informal 
(non-reported  in  QST)  conferences  at  wliich  most 
items  are  fairly  well  firmed-up  and  prepared  for  the 
''formal*'  reportable  meeting.  This  May  meeting 
was  not  marred  by  *^committee  of  the  whole" 
tactics.  Several  recesses  were  called  for  the  purpose 
of  discussion,  off  the  record,  and  other  necessary 
rest  periods* 

A  second  meeting  each  year,  if  made  official 
and  acted  upon  yearly  (after  '69)^  will  be  one  of 
the  most  lasting  and  beneficial  acts  of  the  May 
meeting.  The  ARRL  has  long  suffered  from  a 
communications  gap  with  a  year  between  meetings. 
This  has  often  resulted  in  permitting  the  Exec. 
Co  mm.  (which  meets  frequently)  to  act  without 
referral  to  the  full  Board  or  to  handle  matters 
which  should  be  Board-controlled. 

A  single  yearly  meeting  for  a  megabuck  corp- 
oration, is  less  than  justifiable.  This  demand  for  a 
second  meeting  is  commended.  It  is  truly  a  step 
forward  in  directorship.  If  directors  meeting  in 
November  wiU  study  the  minutes  of  the  May 
meeting  as  well  as  those  of  recent  years  and 
foilow^thru  on  some  of  the  unfinished  business 
(tabled  or  otherwise)  something  of  value  may  be 
achieved. 


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SB400     .... 

275.00 

.  .  .  PSA300  Delujtf 

JOHNSON 

Sl  ps    ... 
Du6-B[id84 

.  75.00 

Viking  11  ... 

*  69.*>0 

129.00 

500  , 

275.00 

AC35 

.  59. OO 

Valiant  11    ., 

,  75.00 

UAC35 

.  79. OO 

Viiiiant  , 

110/JO 

RVl 

.  .  49.00 

250-33  Af   .  . 

.  35.00 

GaUxy  [11  .  . 
GONSET 

1 79.00 

Pacemaker    . 

139,00 

122  VFO    .  . 

.  19.O0 

G^3    ..... 

.  .49.00 

Cli^enger    . 

50.00 

H  A  LLICE  AFTERS 

Viking  xmtr. 

VF0^10-!5'^ 

■           V    i     *    < 

SX-9ti  . 

119.00 

119.00 

SX-9B  .  .     .. 

-  79.00 

.N0.241J-141 

i>y.oo 

SX^llO 

.  99.00 

Dynamo  tor 

S^5 

.  59,00 

289104    .  . 

.  49.00 

S-J  20    , 

*  35.00 

VFO  2I0-I52'n9.0t 

SXlOl     .     _ 

189.00 

Adventurer  , 

,  15.00 

SX^lOl    .... 

189.00 

Vikitie  fiN2  . 

.  75.00 

SX-11  1    _  . 

119,00 

RangiT    .... 

.70.00 

HT-40  _  .     . 

.  50.00 

KNIGHT 

SX*i08  .... 

.  S9,00 

T60 

.  29.00 

SX-100 

125.00 

TI50    ...•. 

.  59.0< 
149.0{ 

HT-41  ..... 

I99.O0 

TRIOS    .... 

SR2000 

RF  Ken  .... 

.  29.00 

K  100.\ 

VKO 

LAFAYt:TT|: 
HE  30 

K  £50 

H  .\9t) 

l-lE45Ii   .  .  .  .  . 
flEi>IA  VFO 
MOSLEY 

^.-    p  ^  J    mJ       !■      ■.      ■       »     ita      I 

NATIONAL 

NCa73    .... 
NCi55  . 

NCI  88 
NCI 09    .... 

HaOaOT  .  .  . 
N'CX5  Markl  1395.00 
NCXA  .....  85.00 
NCXo  V¥'0  149.00 
IVCX500  & 

AC50O    .  .  .  449.00 
POLY*COMM 


25.^10 
ri9.0t) 
19.00 

30,00 
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24.00 
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,  69. OO 

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*i9.00 
,  50 -OO 
129.00 


175.00 
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.  34.00 

.49.00 
.  69.0t> 
.  25.00 

59.00 


.00 
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.00 
.00 
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H.ME 

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SW.-^N   EJec ironies 

117AC    ,  ,  .  .  .  69,00 

406  ....,_,  45. 

TCU  240  VFO  69 

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350 .  295. 

500  .......  395. 

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1 


OCTOBER    1969 


79 


f 


The  agenda  of  the  November  meeting  contains 
controversial  items  and  the  meeting  should  be  most 
intriguing! 

rtem  76  lists  budgets  for  administrative  ex- 
penses of  directors  for  '69.  These  amounts  are  set 
by  the  individual  director  v^ho  may  request  any 
amount  deemed  necessary  to  spend  in  the  interests 
of  ARRL  in  his  division.  These  amounts  range 
from  $1000  to  $3200. 

With  the  high  cost  of  travel  and  printing,  it 
appears  that  these  figures  are  (for  the  most  part) 
puny.  There  would  be  no  objection  if  any  director 
raised  his  expense  figures  although  when  this 
reporter  was  a  director  there  was  some  effort  on 
the  part  of  many  directors  to  see  just  how  cheap  he 
could  be  in  his  directorship,  rather  than  see  what 
was  needed  to  really  do  a  job  of  representation  and 
request  sufficient  money  to  do  the  job. 

Many  directors  must  spend  money  out  of  their 
own  pockets  to  fulfill  their  responsibilities  and  this 
does  not  seem  proper  when  the  ARRL  gross 
income  is  large  (1968 -SI, 498,5 74.62)  and  the 
need  for  better  and  more  extensive  communication 
between  director  and  member  is  so  prevalent.  With 
larger  budget  authority  each  director  could  more 
effectively  represent  ARRL  in  the  field. 

Item  34  provides  vice  directors  with  advance 
copies  of  QST  each  month.  Now,  that  is  a 
magnanimous  gesture  on  the  part  of  the  directors- 
At  least  vice  directors  get  that  much  out  of  their 
almost  non-existent  duties.  ARRL  officers  receive 
no  salary. 

One  of  the  motions  that  can  usually  be  counted 
upon  at  each  Board  meeting  is  contained  in  Item 
92.  This  motion  called  for  authorization  to  permit 
vice  directors  to  attend  (at  League  expense)  one 
Board  meeting  during  a  two-year  term  of  office. 
This  long-needed  authorization  was  defeated  by  a 
vote  of  9  no -7  yes! 

The  thinking  of  those  nine  directors  must  be 
fuzzy.  Why  would  not  they  welcome  the  presence 
of  vice  directors  at  the  Board  meeting  so  they 
could  see  what  goes  on,  first  hand,  at  these 
meetings.  Many  cannot  afford  to  do  this.  Vic^ 
directors  can  only  monitor  the  meetings  anyway, 
and  have  little  or  no  voice. 

Vice  directors,  could  if  allowed  and  encouraged 
to  do  so,  become  a  vital  part  of  the  activities  of 
ARRL  pohcy-making-  But  NO!  Not  only  are  they 
excluded  from  such  opportunities  they  are  forced 
to  either  pay  their  own  way  or  obtain  funds 
elsewhere  to  attend  a  convention  or  meeting.  It  is 
time  that  vice  directors  were  recognized  and 
brought  into  the  ARRL  political  picture  and 
activity  to  the  fullest  extent.  Their  talents  are 
badly  needed  in  the  field! 

Ironical  as  it  may  appear  the  ill-fated  motion  in 
Item  92  was  followed  by  a  unanimous  vote  of 
appreciation  by  the  Board  for  the  several  vice 
directors  present-ad  nauseam!  Such  a  motion 
seems  rather  puerile  and  in  the  case  of  nine 
directors,  penurious! 

Electioneering-Items  10  and  70  provide  an- 
other example  of  Board  stalling  by  referral  to  a 
committee  of  a  sticky  problem* 

Item  10  caUs  for  procedure  wherein  candidates 
(for  director  or  vice  director)  would  furnish  HQ 
written  information  concerning  his  qualifications 
(not  more  than  200  words)  and  a  list  of  his 
amateur  radio  affiliations.  This  material  was  not  to 
contain  any  derogatory  (by  innuendo  or  directly) 
statements  regarding  any  opponent  for  the  office. 
This  material   to  be  prepared  with   a   phpto  (if 


supplied)  in  a  standard  size  sheet  for  each  can- 
didate  so  furnishing  the  information,  and  pub- 
lished, with  no  HQ  editing,  then  enclosed  with  the 
ballot  sent  each  potential  voter.  The  same  item 
provided  that  no  lists  of  names  and  addresses  or 
addressed  envelopes  be  supplied  to  any  candidate 
or  his  committee  or  to  anyone  for  electioneering 
purposes.  This  motion  was  tabled  by  a  unanimous 
vote. 

Another  stall  was  made  when  in  item  70,  the 
same  director  presented  an  almost  similar  motion, 
albeit  shortened,  with  the  same  motive.  Another 
amendment  assigned  the  matter  to  the  Planning 
Committee  for  study.  This  amendment  passed 
10-5,  The  whole  idea  was  then  demoted  to  a 
"study  of  election  procedures  by  the  Committee*' 
by  another  unanimous  vote. 

A  uaiform  electioneering  literature  release,  with 
the  ballot,  would  be  beneficial  and  would  save 
much  expense  on  the  part  of  electioneering  groups, 
provided,  of  course  that  HQ  did  not  censor  or  edit 
such  material  submitted  and  that  no  difficulties 
arose  as  to  what  constituted  '^derogatory  remarks/* 
etc.  All  candidates  would  therefore  have  the  same 
opportunity  for  exposure,  at  less  expense,  than 
with  the  present  method  wliich  is  unfair  in  that  it 
gives  a  break  to  any  candidate  able  to  raise 
sufficient  funds  to  widely  advertise  and  also 
deprives  candidates  not  so  fortunate,  who  may  be 
just  as  quahfied  for  the  office.  Holding  any  ARRL 
office  should  not  be  contingent  upon  how  much 
money  a  candidate  or  liis  supporters  can  raise. 

This  reporter  hopefully  looks  for  this  reform  at 
the  earliest  opportunity.  And,  that  the  intent  of 
the  original  motion  be  preserved,  in  toto! 

Item  46  is  a  somewhat  confused  attempt  to 
secure  redress  through  a  committee  of  teUers  for 
unfair,  unethical  or  otherwise  undesireable  action 
by,  or  on  behalf  of  an  opposing  candidate.  Such 
complaint  to  be  made  in  writing.  A  move  to  table 
was  lost  as  there  was  no  second.  After  more 
discussion,  anoliier  tabling  motion  passed,  12-4, 

The  thinking  behind  tliis  motion  may  be  well 
founded  but  the  intricities  of  handling  such  a 
complaint  would  challenge  the  mind  of  a  Solomon. 
Regardless  of  that  fact*  tabling  such  a  motion 
solves  nothing  and  is  an  indecisive  way  of  handling 
a  hot  potato  but  indicative  of  the  lack  of  direct 
action  displayed  by  the  Board  on  such  occasions* 
Sort  of  reminds  one  of  the  Congress!  Sweep  it 
under  the  rug,  boys,  and  forget  it! 

Communications  Department- In  Item  59,  the 
Board  created  a  five-band  WAS  award  to  be 
initiated  by  the  Comm.  Dept,  and  effective  after  its 
availability. 

This  is  an  excellent  award  idea  and  should 
create  a  lot  of  interest  in  domestic  operation  but  it 
is  hardly  a  matter  for  deliberation  by  the  directors 
of  a  megabuck  corporation. 

Why  did  not  the  Comm.  Dept.  just  up  and 
create  this  miracle  and  put  it  into  use?  Perhaps  it 
was  not  their  idea  at  all,  and  it  does  mean  more 
work  for  the  Comm,  Dept  J 

Those  seeking  credit  for  their  personal  net 
accomplishments  will  be  pleased  to  learn  that 
ARRL's  Comm.  Dept,  will  now  recognize  (a)  net 
check-ins;  (b)  net  control  duties;  (c)  net  liaison 
duties;  (d)  Emergency  Corps  participation;  (e) 
phone  patch  operation-  Points  are  to  be  estabUshed 
and  reported  in  QST  by  SCM$.  This  motion  was 
unanimously  accepted  in  Item  65. 

This  reporter  is  fully  aware  of  the  importance 
of  certam  types  of  net  operation  and  the  training 


80 


73  MAGAZINE 


value  contained  in  some  nets  and  does  not  belittle 
such  activity.  It  does  appear  that  QST  space  could 
be  better  occupied  with  articles  on  net  operation 
and  net  concepts  of  general  information  to  all,  thus 
stimulating  more  interest  in  and  understanding  of 
the  motives  and  practices  of  the  better  class  of 
nets. 

The  point  standings  could  be  better  handled  in 
the  Comm,  Dept.  voluminous  bulletins  sent  to 
those  interested  rather  than  take  away  QST  space 
from  technicaJ  and  other  valuable  material.  Only  a 
few  QST  readers  have  interest  in  traffic  matters. 

What  a  comedown  for  the  Co  mm.  Dept.  to  have 
to  recognize  phone  patching  and  to  have  to  issue 
points  for  it.  Wow! 

Stand  by  for  a  cut  in  readable  QST  space  and 
an  appropriation  for  computer  rental! 

The  Board,  after  deliberation,  established  the 

ICAO    phonetic  alnhabet  (Item  63)  as  approved 
Now  to  get  the  lads  to  use  it-or  any  other 

standard  phonetics.  It  is  unlikely  that  ARRL 
approval  is  going  to  reduce  or  change  the  silly 
practice  followed  by  so  many  with  their  inane  and 
confusing  self-established  phonetics* 

Item  82  will  change  the  rules -to  require  that 
candidates  for  SCM  must  have  been  a  Full  Member 
of  ARRL  and,  to  have  held  a  General,  Conditional 
or  higher  license,  for  two  years. 

This  is  a  good  move  designed  to  insure  better 
qualified  persons  in  this  important,  unpaid  and 
difficult  task  of  being  an  SCiM, 

Item  83  places  the  determination  of  the  stand- 
ards of  quaHfications  for  an  00  to  be  the 
responsibility  of  the  Comm.  Dept.  Manager.  00- 
— Official  Observer-a  volunteer  Grand  Island-type, 
with  no  authority  or  back-up  to  cause  operators  to 
"fly  right."  SCM- Section  Communications  Mana- 
ger-a  volunteer  unpaid  local  representative  of 
ARRL  at  state  or  geographical  levet  Reports  in 
QST  and  bandies  traffic  matters  for  his  area. 

Contestees  will  delight  in  Item  33  and  all  others 
(a  majority)  wiU  climb  the  nearest  wall!  This  item 
proposes  a  Comm,  Dept.  party  once  a  year  in 
which  members  are  invited  to  work  the  Leaguers 
official  family  of  officers  or  appointees. 

There  used  to  be  a  similar  type  contest  called 
LO  Nite  (League  Officers  Night)  and  it  is  sunnised 
that  this  new  bit  of  QRM-making  ** togetherness" 
may  be  in  addition  to  LO  Nite. 

This  reporter  wonders  if  certain  League  officials 
will  answer  pointed  questions  during  these  QSOs? 
Let's  find  out! 

SCMS  and  the  Board -Item  18  instructs  the 
General  Manager  to  furnish  each  SCM  (at  his 
request  and  at  ARRL  expense)  a  set  of  training  and 
operating  manuals-  The  SCMs  are  perhaps  the 
hardest  working  members  of  the  L(3,  and  they 
must  be  a  real  hardy  breed! 

ARRL  and  its  AffiUated  Clubs-Item  16  (which 
failed  to  pass  due  to  no  second)  would  have 
furnished  a  free  sub  to  QST  to  any  affiliated  club 
who  could  produce  ten  members  of  ARRL  who 
would  sign  such  a  request.  The  loss  of  this  motion, 
due  to  failure  of  a  second,  is  lamentable  and  sure  is 
poor  PR! 

ARRL  and  the  DXCC-The  Board  again  delved 
into  petty  non-Board  deliberations  when  (in  Item 
47-passed)  it  permits  DXCC  members  to  submit 
QSLs  in  increments  of  10  after  250  countries  have 
been  credited*  A  worthy  idea-but  hardly  a  matter 
for  Board  consideration. 

Item  56  attempted  to  secure  a  unified  countries  , 


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list.  After  several  amendments  and  much  deliberd- 
tion  the  following  was  adopted -"that  the  Presi- 
dent and  General  Manager  study  the  feasibility  of 
implimenting  preparation  of  a  countries  Mst  jointly 
prepared  by  lARU  societies." 

This  will  solve  nothing!  Many  of  the  important 
countries  lists  (and  awards)  are  made  by  groups, 
organizations  or  publications  who  aie  not  lARU 
members.  The  original  motion  was  well-organized 
and  important.  Read  it  in  QST  and  see  for 
yourself.  It  should  have  been  passed  without 
debate.  Now  sometime  we  may  have  an  lARU  list, 
which  will  be  dominated  by  ARRL's  DX  clique^ 
and  it  will  be  ineffectual! 

In  the  *50s  this  reporter  advocated  and  fought 
for  a  DX  committee  with  representatives  of  leading 
ham  organizations,  DX  clubs  and  publications.  Tliis 
idea  was  defeated.  Result— utter  confusion  in  the 
DX  ranks  as  to  what,  where*  when  is  a  country.  By 
the  beaid  of  TOM-tliis  IS  a  Rotten  Mess! 

ARRL  Foundation-Item  28  instructs  the  Gen- 
eral   Manager    and    Counsel    to    promulgate    the 

establishment  of  the  ARRL  Foundation,  as  a 
separate  non-profit  corporation.  Objectives  and 
purposes  to  provide  ways  and  means  for  perma- 
nently establishing  authority  to  utilize  special 
funds  and  property  of  the  Foundation  and  income 
therefrom  under  restrictions  as  might  be  imposed. 
(The  motion  is  long  and  wordy  and  does  not 
coinside  with  the  version  given  in  League  Lines 
June  QST),  The  Foundation  would  be  managed  by 
a  Board  consisting  of  the  ARRL  President^  Treas- 
urer and  Secretary  plus  other  director-elected 
members. 

The  basic  idea  appears  to  be  a  means  whereby 
ARRL  can  receive  funds  (gjfts,  bequests,  etc.)  and 
expend  them  as  a  separate  corporation  from  ARRL 
Inc.  The  outcome  of  tliis  excellent  idea  will  be 
forthcoming  in  November. 

It  is  hoped  that  the  Foundation  will  not  be  as 
miserly  as  is  the  official  body  of  the  parent 
corporation  when  it  comes  to  advancing  the  state 


of  the   art   of  amateur  radio   and    stimulation 

thereof! 

ARRL  and  Assistance  to  Foreign  Amateurs - 
Item  S2  voted  unanimously  that  ARRL  continue 
its  program  of  assistance,  etc. 

There  is  no  quarrel  with  this  motion  except 
that  ubiquitous  word  continue.  Study  of  past 
ARRL  affairs  reveals  little  that  has  been  done  in 
this  line  and  to  continue  along  the  present  path  of 
'*assistance"  does  not  seem  to  be  of  much  value  to 
anyone,  ARRL  could  and  should  do  a  great  deal  in 
this  line-but  like  many,  this  reporter  believes  that 
charity  begins  at  home.  Perliaps  a  communications 
gap  exists  between  HQ  and  the  reader-membership 
or  perhaps  it  is  another  example  of  the  familar 
phrase— credibility  gap! 

Conspicuous  by  its  absence  was  reference  to  the 
ARRL  Space  Station  ordered  installed  under  Item 
24^  1967  minutes  J  unless  Item  67  can  be  so 
construed  as  to  that  station  to  be  located  at 
OSCAR  HQ.  No  mention  could  be  found  in  the  '68 
minutes  of  the  Space  Station- 

Another  matter  not  mentioned  in  *69  minutes 
was  the  ARRL  out-going  DX  CJSL  bureau  as 
discussed  in  Item  37  of  the  *67  minutes,  A  study 
and  report  was  ordered  (Item  17 -'68)  and  was 
given  to  the  Executive  Committee  Jan.  1,  1969, 
meeting  325.  The  committee  unanimously  voted 
against  the  establishment  of  such  a  bureau  conclud- 
ing "that  it  would  be  in   the  best  interests  of 

amateur  radio  not  to  expand  the  existing  system," 

The  existing  system  is  that  of  HQ  receiving 
incoming  QSLs  and  sending  them  to  unpaid  volun- 
teer bureaus  who  mail  cards  to  those  having 
envelopes  on  file  in  the  bureau. 

This  incoming  system  is  excellent  due  to  the 
hard-working  and  tireless  group  of  volunteers  but 
ARRL  (the  largest  and  most  wealthy)  amateur 
radio  organization  in  the  free  world  should  long 
ago  have  established  an  outgoing  DX  QSL  system. 

The  Executive  Committee  decision  appears  to 
be  another  example  of  abrogation  of  responsibili- 
ties by  the  Board  who  passed  the  buck  to  the  Exec. 
Comm.  whose  record  in  the  past  has  been  toward 
the  reactionary  side. 

There  are  at  least  two  out-going  QSL  bureaus 
doing  business  at  this  time.  Perhaps  DXers  are 
better  off  dealing  with  "private  enterprise"  than 
with  an  agency*  especially  if  it  does  not  want  to  do 
the  job. 

In  addition  to  the  above  items  the  Board 
considered  and  acted  upon  various  other  matters  in 
one  way  or  another.  Most  did  not  seem  of 
sufficient  import  to  be  reported  here, 

A  sincere  effort  was  made  to  preserve  the  intent 
and  meaning  of  each  motion  discussed.  Although 
some  were  paraphrased  for  brevity,  in  no  case  was 
any  idea  or  motive  deliberately  distorted  or  taken 
out  of  context. 

Deliberations  and  decisions  of  the  ARRL  Board 
of  Directors  (as  well  as  those  of  the  Executive 
Committee)  affect  ALL  amateurs  and  AR.  You  are 
urged  to  carefully  study  the  minutes  in  July  QST 
and,  with  this  commentary  at  hand,  attempt  to 
reach  your  own  conclusions  as  to  the  results  of  this 
meeting. 

A  ball-park  estimate  of  the  items  in  the  entire 
proceedings  resulted  in  a  tally  of  38  that  were 
beneficial,  in  one  way  or  another,  to  AR,  and  there 
were  16  that  were  considered  negative.  You  can 
make  your  own  tally  after  digesting  the  minutes. 

. . .  W7ZC 


82 


73  MAGAZINE 


Ear!  Spence  K4FQU 
1413  Davis  Drive 
Fort  Myers,  FL  33901 


Power 


Many  of  the  transceivers  on  the  market 
oday  are  packaged  separately  from  the 
lower  suppUes.  The  easiest  way  out  is,  of 
ourse,  to  pay  the  $100  (or  so)  and  buy  the 
»ower  supply  along  with  the  transceiver. 

But  if  you  happen  either  to  be  obstinate 
ff  hold  that  $100  in  a  little  more  awe  than 
eems  to  be  average  these  days,  you  might 
/ant  to  follow  my  lead  and  build  your  own 
>ower  supply. 

First,  let  us  examine  what  is  needed  in  a 
rower  supply  capable  of  powering  an  SSB 
ransceiver  of  the  NCX  Class.  Most  similar 
igs  utilize  about  the  same  voltages  and 
urrents.  We  find  that  my  rig  required  a  final 
ilate  voltage  of  about  700  vdc  at  300  ma 
^hich  is  maximum  current  under  load.  A 
lias  of  80  vdc  negative  at  6  ma,  280  vdc 
upply  at  200  ma,  and  of  course  filaments, 
nake  up  the  balance  of  the  needed  voltages, 
This  is  not  a  lot  of  power  and  can  easily  be 
urnished  with  a  good  husky  TV  trans- 
or  men  The  transformer  is  the  most  expen- 
ive  portion  of  a  power  supply  and,  natu- 
ally,  the  most  important,  so  care  should  be 
aken  in  choosing  it.  Test  the  one  you  select 
o  make  certain  it  will  deliver  under  pro- 
onged  load  without  overheating.  It  is  far 
:asier  to  check  before  than  after  the  supply 
s  finished.  Keep  in  mind  that  the  trans- 
brmer  has  to  produce  fuO  voltages  under 
*EP  conditions  so  the  full  drain  even  at  top 
oad  is  not  extremely  heavy.  Therefore  don*t 
>verlook  a  transformer  just  because  it  is  not 
IS  big  as  a  bread  box. 


My  junk  box  produced  a  number  of  likely 
looking  transformers,  but  none  had  just  the 
light  voltages.  A  Uttle  scrounging  in  a 
friend's  junk  box  turned  up  one  which  did. 
It  was  center-tapped,  produced  about  750 
volts  across  the  winding  and  was  large 
enough  to  gamble  on  its  providing  the 
needed  current.  It  also  had  three  filament 
windings  which  are  used  for  the  bias  trans- 
former and  the  filaments.  The  bias  trans- 
former is  a  cheap  6.3  volt  fUament  trans- 
former and  is  run  backwards  off  the  5  volt 
winding  of  the  power  transformer  to 
produce  about  100  volts. 

The  output  high  voltage  of  the  power 
transformer  was  a  little  over  700  volts  using 
a  solid  state  bridge  rectifier  and  the  center- 
tap  was  used  for  the  low  B+  supply.  Al- 
though theoretically  the  center-tap  should 
have  produced  about  350  volts,  this  one 
only  ran  300  and  dropped  under  load  to  285 
volts  • .  .  just  about  on  the  nose. 


1  shows  that  the  circuit  is  clean  and 
straightforward  and  not  of  unusual  or  new 
design.  It  should  be  quite  easy  to  under- 
stand, even  to  those  of  us  with  limited 
knowledge.  Notice  the  bias  supply  in  par- 
ticular; This  is  an  easy  method  of  obtaining 
negative  voltages  and  has  been  used  in  many 
similar  circuits.  The  output  of  the  reversed 
filament  transformer  is  rectified  by  a  single 
diode  of  the  same  type  and  ratings  as  those 
in  the  bridge  network.  Although  I  included  a 
variable   pot  in  this  bias  supply^  it  is  not 


»CTOBER    1969 


83 


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dt  30O(TH3 

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+  700  VDC 
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■<r\j>— '    j^ 


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+  Z80V0C 


JOflt 
450  V 


fN740 


IIOV 
T-2 


£OMt 
200V 


5K 


O-0OVDC 
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25W 


Uav 


6.3V 


-*  iaeV  FILS. 


-COMMON 

1 


Fig.    1,      The  schematic  for  the  cheap  and   easy  power  supply- 


needed  for  the  NCX-5  as  it  has  a  pot  for  this 
on  the  rear  apron.  Mine  was  included,  since 
the  supply  is  used  on  occasion  as  a  bench 
supply.  You  may  elect  to  do  without  it. 

Physically  the  supply  is  small  though 
quite  heavy  (about  35  pounds)  due  mostly 
to  the  transformer  and  the  two  chokes.  It  is 
built  ona2x8xlO  inches  aluminum  chassis 
with  the  transformer  and  two  chokes  mount- 
ed on  the  top  along  with  the  bridge  network. 
It  has  enough  room  to  include  the  speaker  if 
you  wish.  Control  circuitry,  filters  and  bias 
transformer  are  mounted  under  the  chassis 
with  lots  of  room  for  large  fingers*  All  con- 
nectors are  brought  out  one  end  of  the  chassis 
and  include  a  nine  pin  Jones  connector,  an 
RCA  phono  plug  for  the  speaker  lead,  the  bias 
pot  and  the  ac  line.  No  switch  is  required  in 
the  ac  line  as  this  is  done  in  the  transceiver; 
however*  I  have  one  buUt  in  for  bench  use 
which  is  left  in  the  on  position  when  used 
with  the  rig  (not  shown  on  the  schematic). 
The  ac  line  should  be  fused  in  each  leg  per 
standard  safety  measures. 

The  heart  of  the  unit  is  the  diode  bridge 
network  and  a  few  words  are  in  order  about 
the  subject.  All  diodes  are  the  top  hat 
variety  and  are  readily  available  in  most  local 
supply  houses  at  about  50  cents  each.  They 
are  rated  at  400  volts  PIV  and  750  mil 
capacity.  This  is  a  full  wave  bridge  using 
three  diodes  in  each  leg  or  twelve  in  alL  Each 


diode  is  protected  by  a  re^stor  and  capacitor 
in  parallel  across  it.  Surge  resistors  are  used 
ahead  of  the  bridge  in  each  leg;  without 
them  you  might  soon  be  replacing  diodes* 

Mount  the  bridge  network  on  a  small 
piece  of  Vector  board  about  2x4  inches.  This 
board  should  be  the  type  on  which  the  lugs 
go  through  the  board  on  both  sides.  Mount 
all  the  diodes  on  the  top  side  of  the  board 
running  around  the  board  so  that  it  is  fed 
from  the  center  on  both  sides.  Ground  and 
the  dc  will  be  from  each  end  of  the  board. 
Mount  the  resistors  and  capacitors  on  the 
under  side  of  the  board  making  sure  that 
they  do  not  short  across  the  board.  Bore  a 
hole  in  each  corner  of  the  board  and  mount 
on  1"  stand-off  insulators.  Be  certain  that 
nothing  shorts  to  ground  or  you  will  have 
smoke! 

The  rest  of  the  supply  is  common  sense 
and  so  nothing  more  will  be  said  about  it. 
Make  a  cover  with  Reynolds  perforated 
aluminum  and  paint  to  match  your  rig.  Take 
care  so  you  can  be  proud  to  say  that  you 
built  it.  This  circuit  and  supply  is  not 
offered  as  the  perfect  solution  to  your 
needs,  however  it  will  suffice  with  minor 
alteration  for  almost  any  modern  200  watt 
SSB  transceiver, 

I  have  been-  using  this  power  supply  for 
about  a  year  now  without  a  moment^s 
trouble.  It  ran  the  NCX-5  for  24  solid  hours 


84 


73   MAGAZINE 


rex 


/ 


The  performance  line  .  .  • 
with  a  material  difference! 


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COMMUNtCATION  ENGINEERS  AND  ADVANCED  AMATEURS 

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tion products ^ — for  Jong  lasting  optimum  performance  and  valye* 
FR€£  .  .  ,  Tech  data  and  pricing  catalogs  describing  off-the-shelf  and  cus- 
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and  rotabte  ^'Berthas'^ 

For  commerciat  and  mifitary  applications  write  for  CM69  ...  for  amateur 
applications  write  for  PL69. 


/ 


rex. 


ASdUHT  PARK, 
NEW  JERSEY  07712.  U.SJI. 


during  last  field  day  and  was  cold  to  the 
touch  at  all  times.  It  just  recently  ran  the  SS 
contest  and  ran  cold  even  after  a  brief 
exchange  with  W2NSD/1.  The  transceiver 
can  be  loaded  to  about  60  mils  over  maxi- 
mum so  it  is  evident  that  there  is  plenty  of 
current,  Plate  voltage  under  full  load  runs  a 
hair  imder  700  volts.  On  the  air  reports  are 
good  and  it  has  no  noticeable  bogies. 

Total  investment  for  all  parts  that  the 
junk  box  did  not  supply  came  to  about  $18. 
Included  among  these  parts  were  all  the 
diodes,  chassis  and  a  filter  capacitor.  It^s  a 
far  cry  from  the  $110  plus  tax  for  a 
commercial  supply. 

,  .  .  K4FQU 


ANTENNA  SPECIALS 

Hy-gain  was  Special 


was 

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WANTED:     General  Coverage  Receivers 
in  Good  Shape. 

H  C  J  ELECTRONICS 

E.  8214  SPRAGUE 
Spokane,  Wash.  99206 


RENEWAL  CODE 

The  +WO  numbers  urider  your  call  on  the  ad- 
dress label  are  the  expiration  coda*  We  have 
tried  to  make  it  simple.  The  first  number  is  the 
month  that  we  send  you  the  last  copy  on  yaur 
subscription  and  the  second  number  is  the  year, 
78   would    be   July    1968,   for   example. 


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i 

I 


OCTOBER    1969 


35 


Getting  Your  Extra 
Class  License 


Part  IX 


Modulation 


73  STAFF 


One  factor  which  all  forms  of  communi- 
cations share  is  ^'modulation."  While  we 
use  the  word,  in  radio,  to  refer  to  a  specific 
process  involved  in  generating  a  signal  for 
transmission^  it^s  used  elsewhere  with  much 
wider  meanings  -  as  for  example  in  the 
phrase  "he  has  a  weU-modulated  voice/* 

Even  if  we  limit  ourselves  to  the  meanings 
of  "modulation"  involved  in  radio,  it's  a 
most  important  subject.  A  m^or  group  of 
questions  in  the  Extra  Class  license  examinar 
tion  study  list  deals  with  various  specifics  of 
modulation  -  and  that*s  our  subject  this 
time. 

The  FCC*s  study  questions  which  we'll 
cover  are: 

1,  What  are  sideband  frequenci^? 
During  100%  sinusoidal  amplitude  modula- 
tion, what  percentage  of  the  average  power 
is  in  the  sidebands?  How  is  the  sideband 
power  related  to  the  percentage  of  modula- 


2,  What  do  the  modulation  envelopes  of 
amplitude*  modulated  waves  with  75%, 
100%,  and  greater  than  100%  modulation 
look  like? 

18.  Define  the  deviation  ratio  in  a  fre- 
quency modulated  signal. 

19.  What  type  of  signal  will  be  produced 
when  the  output  of  a  reactance  modulator  is 
coupled  to  a  Hartley  oscillator  and  multi- 
plied in  frequency? 

56.  What  is  a  grid-bias  modulated  ampli- 
fier? Should  the  source  of.  fixed  bias  have  a 
high  or  low  internal  resistance?  Explain, 

63.  How  are  reactance  tubes  used? 

As  is  our  usual  custom,  we  won*t  answer 


these  six  specific  questions  directly,  Instead^ 
we'll  paraphrase  them  into  four  questions  of 
much  broader  scope  which  will  cover  the 
details  involved  in  the  official  questions* 

For  a  starter,  we'll  attempt  to  find  out 
"What  is  modulation?**  After  all,  we  can't 
very  weU  examine  the  details  of  anything 
until  we  know  what  we're  trying  to  examine. 
An  adequate  definition  of  modulation ,  also, 
may  help  to  put  the  rest  of  our  discussion 
into  a  proper  framework. 

Having  defined  "modulation,"  we  can 
then  ask  "What  can  we  do  to  a  signal  to 
modulate  it?*'  This  wfll  sort  out  the  various 
forms  of  modulation  into  appropriate  groups 
and,  along  the  way,  wfll  define  the  major 
classes  of  modulation  types. 

When  we  know  what  we  want  to  do,  the 
lo^cal  successor  in  our  list  of  questions  is 
how.  That's  our  third  one:  **How  can  we 
modulate  a  signal?" 

And  finaUy,  having  seen  how  to  produce 
modulated  signals  using  any  of  the  major 
classes  of  modulation  which  are  in  wide  use 
by  hams,  we  need  to  examine  the  charao 
teristics  of  these  modulated  signals.  Our  last 
question  this  time  will  be  "What  are  the 
characteristics  of  a  modulated  signal?" 

WeVe  got  a  lot  of  ground  to  cover  to 
answer  those  four  questions;  we're  on  our 
way! 

What  Is  Modulation?  As  we  observed 
back  at  the  beginning  of  this  installment, 
*  ^modulation''  is  a  word  with  many 
meanings,  and  only  a  few  of  them  are 
applicable  to  radio  communications  in  gen- 
eral or  to  ham  radio  in  particular. 


86 


73   MAGAZINE 


For  radio  usage,  tiie  word  has  been 
defined  many  times  in  many  ways  —  and 
then  applied  with  some  new  meaning  which 
has  made  the  older  definitions  obsolete. 

An  example:  In  1938,  the  Institute  of 
Radio  Engineers  published  an  official  defini- 
tion of  "modulation"  as  being  "the  process 
of  producing  a  wave  some  characteristic  of 
which  varies  as  a  function  of  the  instan- 
taneous value  of  another  wave,  called  the 

wave." 

This  definition  was  adequate  until  the  rise 
of  telemetry,  in  which  the  modulating  signal 
is  as  likely  to  be  a  dc  level  as  it  is  to  be  a 
"wave"  (whatever  a  wave  may  be).  When  the 
modulating  signal  is  a  dc  level,  however,  the 
1939  definition  must  be  interpreted  rather 
liberally  to  be  appHed, 

Neither  does  it  adequately  cover  the 
concept  that  what  we  call  CW  is  actually 
ampUtude  modulation  (see  last  month's 
installment  for  a  discussion  of  this 
idea)  —  and  when  RTTY  is  involved,  it  gets 
downright  difficult  to  visualize  the  FSK 
signal  as  being  the  product  of  a  "modulating 
wave";  the  definition  had  to  change. 

Another  definition  of  "modulation"  is 
that  given  in  the  Radiotron  Designer's  Hand- 
book^ fourth  edition,  page  1401;  "The 
process  by  which  the  amplitude,  frequency, 
or  phase  of  a  carrier  wave  is  modified  in 
accordance  with  the  characteristics  of  a 
signal" 

This  one,  too,  is  a  bit  short  in  view  of 
modern  practice.  No  SSB  or  other  sup- 
pressed-carrier  signal  could  satisfy  it,  but  no 
one  would  deny  that  a  SSB  signal  is  modu- 
lated. Neither  could  any  type  of  pulse 
modulation  qualify  as  modulation,  under 
this  definition. 

Note  that  neither  of  these  definitions 
dted  as  examples  is  completely  wrong;  the 
trouble  is  that  they^re  merely  incom- 
plete —  and  being  incomplete  is  an  unfor- 
givable sin  in  a  definition. 

What's  needed  is  a  definition  broad 
enough  to  include  not  only  the  types  of 
modulation  used  in  communications  today, 
but  hopefully  aH  future  types  of  modulation 
as  welL  WeVe  had  to  generate  our  own  to 
get  one  that  broad,  but  we  feel  that  it 
accomplishes  the  goal  and  define  modula- 
tion in  such  terms  that  we  can  move  on  to 


more  specific  details. 

Modulation,  as  we  use  the  word  in  this 
installment  at  any  rate,  is  the  transmission  of 
information  by  variation  of  some  charac- 
teristic of  a  transmissible  signal  (which  we 
will  call  the  carrier)  in  such  a  manner  that 
the  original  information  (modulating  signal) 
may  be  recovered  from  the  result  (modu- 
lated signal)  by  a  definable  process  without 
prior  knowledge  of  the  original  information. 

This  does  not  require  that  the  carrier  be 
transmitted  as  a  part  of  the  modulated 
signal;  elimination  of  the  carrier  itself  may 
be  one  of  the  variations  used  to  accomplish 
modulation.  Just  so  long  as  information  is 
transmitted  in  a  manner  which  permits  its 
recovery,  that's  modulation. 

Note  that  this  definition  is  so  broad  that 
a  conventional  land-line  telephone  circuit  or 
intercom  qualifies  as  a  "modulation" 
system*  The  sound  waves  which  are  the 
original  information  vary  the  current  flow  in 
the  connecting  wires;  if  we  consider  the 
at-rest  current  as  "the  carrier,"  then  the 
change  in  current  flow  when  sound  strikes 
the  microphone  provides  "modulation,"  and 
when  the  earphone  or  speaker  changes  this 
current  flow  back  to  sound  waves,  that's  the 
**definable  process"  which  demodulates  the 
signal.  It's  hard  to  get  much  broader  than 
that  while  remaining  specific  enought  to  be 
useful 

In  practice,  though,  we  don't  deal  very 
much  with  intercoms  or  land-lines,  We*re 
radio  operators,  and  we  deal  primarily  in 
radio  signals.  Our  "carrier"  signals,  then,  will 
most  often  be  radio  waves. 

Our  definition  of  modulation  permits  us 
to  vary  any  characteristic  of  our  carrier  in 
order  to  apply  the  modulation.  Let's  see 
what  characteristics  of  a  radio  signal  we  can 
vary  in  order  to  modulate  that  signal. 

What  Can  We  Do  To  A  Signal  To  Modu- 
late It?  We've  agreed  that  our  carrier  signals 
are^  most  often,  radio  waves,  and  our  defini- 
tion of  modulation  permits  us  to  vary  any 
characteristic  of  the  carrier  to  apply  modula- 
tion just  so  long  as  we  can  recover  the 
original  information  from  the  modulated 
signal  by  some  definable  process. 

So  the  first  step  in  deciding  what  charac- 
teristics of  a  radio  signal  we  can  vary  to 
apply   modulation  is  to   decide  just  what 


1 


OCTOBER    1969 


87 


characteristics  a  carrier  has  in  the  fust  place. 

A  conventional  ./  carrier  is  a  single 
frequency  radio  wave;  some  attempts  have 
been  made  to  apply  modulation  to  non- 
coherent or  "noise"  earners,  but  that's  far 
from  general  practice  (and  no  one  has 
publicly  reported  any  success  in  these 
attempts  so  far  as  we  have  been  able  to 
learn).  Such  a  single- frequency  if  wave  has 
three  major  characteristics:  amplitude,  or  its 
strength  relative  to  some  scale  of  measure- 
ment; frequency,  or  its  timing  relative  to 
itself  i  and  phase,  or  its  timing  relative  to  an 
arbitrary  starting  time. 

In  addition  to  the  three  m^or  charac- 
teristics of  ampEtude,  frequency,  and  phase, 
there's  an  even  more  fundamental  charac- 
teristic of  its  existence  at  all.  If  the  wave 
does  not  have  the  characteristic  of  "exist- 
ence," it  has  no  other  characteristics  at  all. 
This  might  appear  to  be  a  merely  philo 
sophical  point  —  and  at  this  level  of 
examination  it  is.  But  if  we  accept  "exist- 
ence" as  a  characteristic,  we  can  then  extend 
this  idea  to  accept  a  **pattern  of  existence" 
as  a  special  form  of  the  "existence"  charac- 
teristic; and  this  opens  the  door  to  the 
exotic  forms  of  pulse  modulation  which 
convey  information,  not  by  the  frequency  or 
ampUtude  of  the  carrier  involved,  but  by  the 
patterns  in  which  the  carrier  either  exists  or 
fails  to  exist. 

We  won*t  labor  this  point  very  much, 
because  pulse  modulation  is  illegal  on  the 
most  popular  amateur  bands,  and  we  have 
more  than  enough  to  attempt  to  cover 
without  getting  into  pulse  work  too  deeply. 
We  must,  however,  note  it  in  passing  in  order 
to  be  complete. 

The  three  m^or  characteristics  which  are 
varied  in  the  most  popular  types  of  modula- 
tion are  illustrated  in  Fig.  1 . 

When  we  vary  any  one  of  these  charac- 
teristics to  modulate  our  carrier,  the  re- 
sulting signal  is  identified  according  to  the 
characteristic  which  we  vary.  If  we  vary  the 
amplitude,  we  produce  amplitude  modula- 
tion or  AM.  Both  SSB  and  DSB  are  special 
cases  of  AM,  in  which  amplitude  is  varied 
but  in  addition  the  carrier  itself  (and  in  SSB, 
one  sideband  as  well)  is  suppressed  from  the 
final  modulated  signal.  If  we  vary  the  fre- 
quency, we  have  frequency  modulation  or 


AMPtiTUDE 


(FREOUENCY)     pHASE 


Fig.  t.  The  three  characterUtics  of  an  ac 
slne-wave  signal  which  may  be  varied  to 
produce  modulation  are  shown  here.  AmpH- 
tude  refers  to  the  peak -to  peak  strength  of 
the  signal  and  may  be  measured  in  either 
volts  or  as  current,  so  long  as  all  references 
are  consistent.  Period  is  the  time  between 
two  points  of  similarity  in  the  waveform, 
such  as  the  two  zero-crossings  shown;  fre- 
quency is  the  reciprocal  of  period  and  is 
simply  the  number  of  cycles  per  unit  of 
time.  Phase  is  the  timing  between  the  signal 
itself  and  some  arbitrary  reference  of  tdenti- 
cdl  period  or  frequency. 

FM.  And  if  we  vary  the  phase,  we  have  phase 
modulation  or  PM. 

Fig*  2  shows  a  theoretical  circuit  which 
can  be  used  to  illustrate  the  differences 
between  AM,  FM,  and  FM,  This  circuit 
consists  of  an  ac  alternator  driven  by  a  dc 
motor,  together  with  separate  controls  for 
the  power  appUed  to  the  dc  motor  and  to 
the  alternator's  field  coils  (the  power  level  in 
the  field  coil  of  an  alternator  or  a  generator 
controls  the  power  level  produced  by  the 
device). 


DC 
1*1  PUT 


AC  OUTPUT 


ALTERNATOR 


DC  MOTOR 


Fig,  2.  Th?s  motor*alternator  circuit  illus- 
trates the  differences  between  the  major 
types  of  modusltion;  it  wouldn't  work  in 
practice  because  of  the  inertia  of  the  moving 
parts,  but  it  gives  an  idea  of  the  principles 
involved* 

Before  we  use  this  circuit  to  illustrate  the 
three  major  types  of  modulation,  let*s  brush 
up  rapidly  on  some  of  the  most  basic  facts 
of  ac  power  generation  by  means  of  alteraar 
tors*  After  all,  it's  not  one  of  the  things  we 
usually  concentrate  upon  as  hams. 

The  major  difference  between  an  alter- 
nator and  a  generator  is  that  an  alternator 


88 


73  MAGAZINE 


produces  ac  while  a  generator  puts  out  dc. 
This  difference  is  accomplished  by  the 
absence  of  either  a  commutator  or  brushes 
in  an  alternator.  Instead,  the  output  is  taken 
off  directly  through  slip  rings.  (In  practice, 
the  "field**  of  an  alternator  is  usually  the 
rotating  part,  while  the  ^'armature"  is 
stationary;  this  is  done  because  a  small 
amount  of  field  power  suffices  to  permit  a 
large  amount  of  armature  power  to  be 
generated,  and  the  d^gners  want  to  mini- 
mize the  amount  of  current  which  must  pass 
through  the  slip  rings.) 

Hie  output  power  level,  as  we  mentioned 
a  few  paragraphs  back,  is  controlled  by  the 
amount  of  power  applied  to  the  field 
winding  of  either  an  alternator  or  a  gen- 
erator. 

TTie  output  frequency  of  a  generator  is 
always  dc,  but  ^the  ac  produced  by  an 
alternator  most  have  some  frequency.  The 
altemator's  output  is  virtually  always  pure 
sine-wave  in  form,  and  the  frequency  is 
determined  by  the  speed  of  rotation  of  the 
alternator's  shaft.  The  faster  the  rotation^ 
the  higher  the  frequency  produced. 

Now  let^s  look  at  the  arrangement  shown 
in  Fig.  2y  and  imagine  that  the  whole 
rotating  system  is  so  light  and  has  so  little 
inertia  that  we  can  change  its  speed  of 
rotation  almost  instantly.  For  a  start, 
though,  let's  adjust  both  Rl  and  R2  to  their 
midpoints  and  take  a  look  at  the  ac  output 
With  both  Rl  and  R2  steady,  the  power 
level  and  the  frequency  of  the  output  will 
remain  constant,  and  the  signal  will  look  Hke 
that  shown  in  Fig.  3. 


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Fig.  3.  If  both  power  controls  in  the  circuit 
of  Fig*  2  are  left  in  mid-positron,  the 
alternator's  output  will  be  constant  in  both 
frequency  and  amplitude,  and  will  in  conse- 
quence be  a  sine-wave  sional  such  as  that 
shown  here.  This  corresponds  to  an  unmod- 
uaited  carrier  stgnatp 

Now  lefs  vary  Rl  from  minimuin  to 
maximum  and  back  regularly,  thus  varying 
the  amount  of  power  applied  to  the  field 
coils  of  the  alternator  and  in  turn  varying 


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«a»7 

90110 


V- 


OCTOBER   1969 


89 


I 


the  output  power  level,  but  leave  R2  set  at 
midpoint  so  that  the  signal  is  still  of  con- 
stant frequency; 


F!g,  4,  If  the  speed  control  is  left  atone  but 
the  figid  power  control  is  varied  regijlarlv 
from  minimum  to  maximum  and  back 
again,  the  output  of  the  alternator  wift  be 
almost  zero  when  field  power  is  minimum 
and  will  increase  as  field  power  Increases 
untti  it  reaches  a  maximum,  then  fall  back 
as  field  power  is  decreased.  The  resulting 
waveform  looks  like  this,  and  corresponds 
to  amplitude  modulation  of  a  constant-fre- 
quency carrier  signal. 

The  result  looks  like  Fig,  4,  The  period 
(which  determines  frequency)  and  the  phase 
remain  the  same  as  in  Fig.  3,  but  the 
amplitude  varies  from  near  zero  to  maxi- 
mimi  and  back  down  again  as  the  field^coil 
power  varies.  This  is  amplitude  modulation. 

For  the  next  illustration,  we'll  leave  Rl 
set  at  midpoint  so  that  output  power  level  is 
constant,  but  vary  R2  at  the  same  rate  as  we 
did  Rl  before.  Assuming  that  the  do  driving 
motor  can  change  speed  instantly  as  we 
change  the  amount  of  power  supplied  to  it, 


F»g.  5,  When  field  power  level  is  left  con- 
stant, but  the  driving  speed  is  varied  from 
high  to  low  and  back,  the  alternator's 
output  win  be  of  constant  amplitude  but 
will  vary  in  frequencv.  This  is  shown  in  this 
waveform;  the  tick  marks  on  the  time  axis 
are  the  times  at  which  the  waveform  of  Fig, 
3  crosses  the  axis,  assuming  that  the  left- 
most zero-crossing  occurs  at  the  same  time 
for  boht  waveforms.  This  corresponds  to 
FM.  All  of  these  waveforms  have  been 
traced  from  an  X-Y  plot  produced  by  an 
electronic  computer,  using  a  carrier  fre- 
quency three  times  that  of  the  modulating 
signal  in  order  to  clearly  show  the  actions. 
Normal  practice  is  to  use  a  carrier  of  several 
hundred  to  several  million  times  the  fre- 
quency of  the  modulating  signal. 


and  that  the  rotating  system  has  so  little 
inertia  that  it  also  can  change  speed 
instantly,  our  output  signal  in  this  case  will 
resemble  Fig,  5. 

The  amplitude  is  constant,  but  the  period 
and  the  phase  both  vary  as  R2  is  varied.  The 
tick  marks  on  'the  baseline  in  Fig.  5  show 
where  the  waveform  of  Fig.  3  crosses  the 
zero  axis.  You  can  see  that  as  the  dc  motor 
turns  faster  and  frequency  rises,  the  period 
of  the  output  signal  shortens,  and  as  it  turns 


AC  OUTPUT 


ALTERNATOR 


Fig.  6.  If  the  circuit  of  Fig.  2  Is  connected 
to  a  constant*frequency  generator  as  shown 
here,  frequency  of  the  output  signal  will  be 
locked  to  that  of  the  second  oenerator. 
Varying  speed  of  the  alternator  now  cannot 
produce  permanent  change  in  frequency^ 
but  will  produce  change  in  phase  of  output 
signal  while  speed  Is  changing.  Result  corres- 
ponds to  PM,  and  has  same  waveform  as  FM 
shown  In  Fig.  5;  differences  between  FM 
and  PM  are  largely  a  matter  of  definitions. 

slower,  the  period  lengthens  again.  This  is 
frequency  modulation. 

We  could  perform  the  same  actions  again 
as  we  did  to  produce  Fig.  5,  but  connect  the 
output  to  a  fixed-frequency  generator 
through  large  series  inductances  as  shown  in 
Fig.  6.  When  we  do  this,  the  frequency  is 
locked  to  that  of  the  fixed-frequency  gen- 
erator —  but  the  phase  will  vary  while  the  dc 
motor's  speed  is  changing.  This  is  phase 
modulation.  We  don't  show  a  separate  illus- 
tration of  it,  because  for  any  single-fre- 
quency modulating  signal,  there  is  essentially 
no  way  to  tell  the  difference  between  FM 
and  PM  at  the  output  signal  The  outputs  of 
each  are  identical. 

The  functional  difference  between  FM 
and  PM  lies  in  the  fact  that  the  amount  of 
change  in  period  or  phase  which  occurs  in 
the  modulated  signal  is  determined  by 
different  factors.  When  FM  is  employed,  the 
amount  of  change  is  determined  by  both  the 
strength  of  the  modulating  signal,  and  by  its 
frequency.     Lower-frequency     modulating 


90 


73  MAGAZINE 


signals  give  greater  change  for  the  same  level 
than  do  higher-frequency  signals.  When  PM 
is  employed^  the  amount  of  change  depends 
only  upon  the  strength  of  the  modulating 
signal. 

There  is  no  practical  difference  between 
the  two  types  of  modulation,  since  any 
filtering  of  the  modulating  signal  ahead  of 
the  point  at  which  modulation  occurs  can 
compensate  for  the  functional  difference 
between  FM  and  PM,  and  permit  an  FM-type 
output  signal  to  be  produced  by  a  PM 
modulator,  or  a  PM  output  signal  to  be 
produced  by  an  FM  modulator.  Most  com- 
mercial FM  broadcasting  uses  an  output 
signal  which  is  about  halfway  between  true 
FM  and  true  PM  characteristics.  Almost  all 
commercial  two-way  FM  equipment  actually 
uses  phase  modulation,  in  order  to  permit 
crystal  control  of  center  frequency. 

How  Can  We  Modulate  A  Signal?  Now 
that  we  have  an  idea  of  the  basic  charac- 
teristics and  differences,  if  any,  between  the 
three  major  types  of  modulation  —  AM,  FM, 
and  PM  —  we  need  to  know  how  we  can 
modulate  a  signal  with  any  of  these  types. 
The  circuit  of  Fig.  2  is  obviously  not  very 
practical  for  use  at  radio  frequencies;  we 
need  something  with  a  lot  less  inertia  than  a 
physical  generator,  and  we  must  be  able  to 
control  it  with  an  audio- frequency  speech 


Let's  see  just  what  we  have  to  work  with, 
and  go  from  there.  If  we're  going  to  modu- 
late a  radio  signal,  we  have  some  type  of  rf 
carrier  generated  by  an  oscillator  and 
brought  up  to  the  output  power  level  we 
desire  by  a  series  of  r/ power  amplifiers,  and 
we  have  some  sort  of  modulating  signal 
which  (except  for  TV)  is  an  af  signal. 
'  To  modulate  that  carrier,  we  must  change 
its  amplitude  if  we  want  AM^  its  frequency  if 
we  want  FM,  or  its  phase  if  we  want  PM, 
Whichever  of  these  characteristics  we 
change,  the  change  must  be  controlled  by 
the  af  modulating  signal. 

We  can  vary  the  amplitude  of  the  signal  in 
either  of  two  basic  ways.  We  can  vary  the 
amount  of  power  supplied  to  one  of  the  rf 
power  amplifier  stages,  or  we  can  vary  the 
operating  efficiency  of  one  of  those  ampli- 
fiers. This  can  be  done  at  any  amplifier 
stage,  but  if  modulation  is  appUed  to  any 


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amplifier  stage  except  the  one  finally  feeding 
the  antenna,  then  special  care  must  be  used 

to  keep  later  amplifiers  from  distorting  the 
modulated  signal  —  that  is,  all  amplifier 
stages  following  the  modulated  one  must  be 
linear. 

We  can  vary  the  frequency  of  the  signal 
by  changing  the  operating  conditions  of  the 
oscillator  which  originally  generates  the 
carrier. 

Phase  of  the  signal  can  be  varied  by 
change  of  operating  conditions  in  any  of  the 
rf  amplifier  stages,  or  by  special  processing 
very  similar  to  the  "phasing"  techniques 
used  to  produce  SSB. 

This  all  sounds  simple  enough,  but  for 
each  of  the  three  basic  types  of  modulation 
an  almost  uncountable  number  of  different 
ways  of  doing  the  job  has  been  developed . 
To  take  AM  as  a  partial  example,  we  can 
apply  the  modulating  signal  to  the  plate,  the 
screen,  the  control  grid,  or  the  cathode  of 
the  rf  amplifier.  If  we  apply  it  to  the  plate, 
we  may  connect  it  by  means  of  a  trans- 
former, an  autotransformer,  or  a  choke.  We 
may  also  combine  any  of  these  connections. 
And  each  of  these  variations  of  AM  has  its 
own  name,  and  its  own  set  of  rules  for 
achieving  the  desired  results. 

Before  we  explore  any  of  the  more 
specific  details  of  the  different  techniques  of 
achieving  AM,  let*s  look  at  some  points 
which  all  of  them  share  in  common* 

To  do  so,  we*ll  take  two  sine- wave  signals; 
their  waveforms  are  shown  on  the  top  two 
lines  of  Fig.  7.  We're  using  a  3-to-l  fre- 
quency ratio  for  these  signals  to  make  the 
illustrations  easier  to  draw;  in  practice,  the 
higher-frequency  signal  normally  is  several 
thousand  to  several  million  times  the  fre- 
quency of  the  lower. 

If  we  apply  either  of  these  signals  by 
itself  to  the  input  of  an  amplifier,  we  will  get 
approximately  the  same  waveform  at  the 
amplifier's  output - 

If  we  apply  both  at  the  same  time  to  the 
input  of  an  amplifier  which  is  reasonably 
free  of  distortion,  the  output  will  look 
something  Uke  the  waveform  shown  on  the 
third  line.  The  highei^lrequency  signal  **rides 
upon*'  the  lower,  but  except  for  that  there's 
no  interaction  between  the  two. 

But    if    the    lower-frequency    signal    is 


e 


Fig,  7,  These  waveforms  illustrate  modylat- 
or  action.  Top  line  (A)  is  carrier  signat  and 
b«low  That  (B)  is  the  positive  half-cycle  of 
the  modulating  signal.  If  both  are  applied  to 
a  linear  amplifier,  output  waveform  win  be 
that  shown  at  C;  carrier  swings  about  the 
low%r-frequency  waveform  (dotted)  rather 
than  around  the  zero  axis.  Moduia  tor's 
action  is  different  (D);  both  signals  swing 
around  ^aro  axis,  but  amplitude  of  carrier  is 
controlled  by  amplitude  of  modulating  sig- 
nal. Object  of  AM  modulation  circuits  is  to 
achieve  waveform  shown  at  D. 

applied  to  the  ampMfier  in  any  manner 
which  causes  the  gain  of  the  amplifier  to 
change  as  a  function  of  that  signal,  and  the 
higher-frequency  one  is  appUed  to  the  input, 
then  the  output  signal  will  resemble  the 
waveform  shown  on  the  bottom  Une. 

As  you  can  see  one  of  the  major  differ- 
ences between  the  lower  two  waveforms  lies 
in  the  "zero  reference"  of  the  high-fre- 
quency signal.  In  the  bottom  waveform, 
both  the  low  and  the  high  frequency  signals 
are  symmetrical  about  the  actual  zero  line, 
but  in  the  next-to-bottom  waveform,  the 
"zero  reference"  of  the  high-frequency 
signal  actually  is  the  waveform  of  the  low- 
frequency  one,  shown  by  the  dotted  line* 

A  linear  amplifier  works  to  produce  the 
effect  shown  on  the  next-to-bottom  wave- 
form; a  modulator  produces  the  bottom 
waveform. 

Note  that  the  requirement  for  producing 
the  modulator-output  waveform  was  that 
the  lower- frequency  signal  —  which  repre^ 
sents  the  modxilating  signal  -  had  to  rause 


92 


73  MAGAZINE 


the  gain  of  the  amplifier  to  change,  while  the 
higher- frequency  signal  -  the  carrier  —  was 
fed  through  from  input  to  output  in  a 
normal  manner. 

One  of  the  simplest  ways  to  change  the 
gain  of  any  amplifier  is  to  change  its  grid 
bias.  This -means  that  we  should  be  able  to 
feed  the  carrier  to  the  amplifier  grid  as  an 
input,  and  the  modulating  signal  to  the  grid 
at  the  same  time  to  vary  the  bias,  and  obtain 
modulating  action.  And,  as  a  matter  of  fact, 
we  can. 

Grid-bias  modulation,  as  such  a  technique 
for  producing  AM  is  called,  has  a  number  of 
characteristics  which  make  it  preferable  to 
any  other  for  some  types  of  signals,  as  well 
as  other  characteristics  which  make  it  unat- 
tractive for  general  use. 

Among  its  advantageous  features  is  the 
fact  that  comparatively  little  power  is  re- 
quired in  the  modulating  signal;  all  that's 
necessary  is  a  voltage  swing  great  enough  to 
produce  the  desired  change  of  bias.  Another 
advantage  is  that  this  technique  is  capable  of 
handling  a  wide  frequency  range  in  the 
modulating  signal,  since  no  transformers  are 
necessary.  This  feature  alone  makes  it  almost 
the  only  way  to  apply  a  video-frequency 
modulating  signal  to  a  carrier,  and  grid-bias 
modulation  is  the  standard  technique  in  TV 
transmission. 

The  same  advantage  is  put  to  use  in  many 
receiver  designs;  any  time  a  receiver  uses  a 
conventional  triode  or  pentode  as  its  mixer 
stage,  with  "control-grid  injection"  of  the 
local-oscillator  signal,  a  grid-bias  modulator 
is  at  work. 

The  disadvantages  which  make  grid-bias 
modulation  unattractive  for  general  AM  use 
include  its  requirement  for  critical  control  of 
operating  conditons.  The  variation  of  bias 
introduced  by  the  modulating  signal  must 
change  the  gain  in  a  more  or  less  linear 
manner  in  order  to  satisfy  the  modulation 
requirement  that  the  original  modulating 
signal  be  recoverable  by  a  definable  process. 
Thai  is,  if  the  positive  peak  of  the  modu- 
lating signal  increases  gain  by  say  20%,  then 
the  negative  peaks  of  the  same  amplitude 
must  reduce  gain  by  the  same  percentage. 
Otherwise  the  modulator's  output  will  not 
be  a  true  representation  of  the  modulating 
signal,  and   any  process  for  recovering  the 


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I 


1 


I 
I 


OCTOBER    1969 


93 


information  won't  get  back  exactly  the  same 
signal  we  started  with.  In  more  conventional 
terms  J  the  modulation  wEl  be  distorted. 

Adding  to  the  problems  of  the  grid-bias 
modulator  is  the  fact  that  the  modulating 
signal  swings  both  positive  and  negative  from 
zero,  while  the  bias  on  a  conventional 
amplifier  must  remain  negative  at  all  times  in 
order  for  the  control  grid  to  retain  control 
of  the  ampHfier's  action.  We  can  take  care  of 
this  by  supplying  a  source  of  fijced  bias, 
which  offsets  the  zero  reference  of  the 
modulating  signal  to  some  fixed  negative 
voltage.  Then  the  actual  grid  bias  will  swing 
from  moderately  negative  to  less  negative 
when  the  modulating  signal  goes  positive, 
and  from  moderately  negative  to  more  nega- 
tive when  the  modulating  signal  takes  a 
negative  swing. 

Since  this  fixed-bias  source  is  electrically 
in  series  with  the  modulating  signal^  it  must 
have  low  internal  resistance.  In  fact,  it  must 
effectively  be  a  dead  short  to  ac  signals  at 
the  lowest  frequency  present  in  the  modu- 
lating signal,  Grid4eak  bias  is  not  suitable;  in 
practice,  it*s  usually  necessary  to  provide 
voltage  regulation  for  the  bias  supply  in 
order  to  keep  the  resistance  low  enough. 

Other  disadvantages  to  grid-bias  modu- 
lation are  that  the  modulated  amphfier  must 
be  adjusted  to  produce  only  one-quarter  of 
its  maximum  rated  output  in  the  absence  of 
modulation;  this  is  necessary  because  at  the 
modulation  peaks,  the  power  output  must 
be  four  times  that  at  no-modulation  levels* 
The  modulated  amplifier's  grid  imposes  a 
varying  load  on  tiie  modulating-signal 
source^  which  can  cause  distortion  of  the 
modulating  signal  before  it  ever  actually 
reaches  the  modulator,  and  the  rf  driver 
supplying  the  carrier  to  the  modulator  must 
be  capable  of  supplying  two  to  four  times  as 
much  power  as  is  normaliy  used,  again  in 
order  to  supply  the  drive  at  the  modulation 
peaks. 

If  a  tetrode  or  pentode  tube  is  used  as  the 
modulated  amplifier,  the  modulating  signal 
can  be  applied  to  its  screen  grid  rather  than 
to  the  control  grid.  Action  is  much  the  same 
as  in  pid-bias  modulation,  but  adjustment  is 
not  so  critical.  Regulation  of  screen  voltage 
is  more  customary  than  is  that  of  grid 
bias  —  and  in  addition  it's  possible  to  achieve 


satisfactory  screen  modulation  without 
regulating  the  voltages.  The  tolerances  in 
screen  modulation  are  great  enough  that 
many  operators  consider  this  the  simplest 
and  least  critical  type  of  grid  modulation. 

Advantages  of  screen  modulation  are  cir- 
cuit simplicity  and  the  need  for  only  a  little 
modulating  power. 

Disadvantages  are  the  need  for  more 
critical  adjustment  (as  compared  to  high- 
level  modulation  which  we*ll  examine  a  httle 
later)  and  reduced  output  power  capabilities. 

All  forms  of  grid  modulation  —  grid-bias 
or  control-grid,  screen,  or  suppressor  —  are 
ways  of  varying  the  amphtude  of  the  output 
signal  by  changing  the  operating  efficiency 
of  the  modulated  amphfier.  Because  of  this, 
all  of  them  must  operate  at  below-normal 
efficiency  in  the  absence  of  modulation,  to 

leave  room  for  modulation  peaks  when  a 
modulating  signal  is  applied.  Most  such 
modulating  schemes  operate  at  about  25% 
efficiency  when  there's  no  modulating 
signal,  and  produce  their  maximum  rated 
output  only  during  the  relatively  infrequent 
positive  peaks  of  modulation. 

It's  possible  to  operate  an  amplifier  at 
nearly  its  maximum  rated  output  in  the 
absence  of  modulating  signal,  and  produce 
up  to  four  times  the  maximum  rated  power 
during  modulation  peaks.  We  can  do  this 
simply  because  the  modulation  peaks  are  so 
infrequent  that  the  amplifier  components 
aren't  damaged  during  the  occasional  over- 
loads. To  do  this,  though,  we  must  stay  far 
enough  below  maximum  rating  in  the  no- 
modulation  or  at-rest  condition  to  permit 
average  modulation  levels  to  stay  inside 
maximum  ratings,  and  we  must  achieve  our 
modulation  by  varying  the  supply  power  to 
the  modulated  stage  rather  than  by  varying 
its  efficiency*  Such  a  modulation  scheme  is 
known  as  high-level  modulation,  and  it's  the 
most  popular  form  of  AM  in  communica- 
tions use. 

High-level  modulation  is  also  called  plate 
modulation,  since  the  power  variations  occur 
in  the  plate  circuit  —  but  if  the  modulated 
state  uses  a  tetrode,  beam-power,  or  pentode 
tube  the  power  to  the  screen  grid  must  be 
varied  right  along  with  that  to  the  plate  in 
order  to  make  things  work. 

This  type  of  modulation  requires  that  the 


94 


73  MAGAZINE 


modulating  signal  be  provided  at  rather 
hefty  power  levels;  the  modulating  signal 
must  supply  half  as  much  power  as  does  the 
dc  supply  during  at-rest  periods.  That  is,  a 
kilowatt  amplifier  that  is  to  be  plate  modu- 
lated requires  a  modulator  capable  of 
supplying  500  watts  of  audio,  and  a  trans- 
mitter operating  with  100  watts  input  (dc) 
requires  5  0  watts  of  audio  from  the  modula- 
tor. 

The  audio  power,  at  audio  frequency,  is 
combined  with  the  dc  power  and  the  result 
is  applied  to  the  modulated  stage.  One  of  the 
most  popular  techniques  for  doing  this  is 
known  as  "series"  plate  modulation  and  is 
shown  in  Fig.  8;  the  ac  from  the  modulating 


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Fig.  8.  Series  plate  modulator,  version. most 

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is  shown  in  this  schematic.  AC  output  irom 
modulator  either  adds  to  or  takes  away 
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signal  is  connected  in  series  with  the  dc  from 
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modulated  stage  receives  the  power  supply's 
dc  output  with  no  modification.  When  a 
modulating  signal  swings  the  ac  positive,  the 
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bucks  out  some  of  the  dc  from  the  power 
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ijr^ 


For  such  a  scheme  to  work,  the  modu- 
lated stage's  output  power  level  must  be 
determined  directly  by  its  dc  power  input 
level;  the  amount  of  input  signal  fed  into  its 
grid  circuit  must  not  be  able  to  affect  power 
output.  As  it  happens^  a  Class  C  amplifier 
that  is  driven  slightly  harder  than  necessary 
to  saturate  it  fulfills  this  requirement.  This 
fact  makes  high-level  series  plate  modulation 
exceptionally  simple  to  adjust. 

It  isn't  necessary  to  connect  the  modu- 
lating signal  in  series  with  the  dc  power 
input  as  shown  in  Fig.  8.  There's  another 
way  of  doing  it  that  gets  by  with  a  little  less 
in  the  way  of  components,  but  is  somewhat 
restricted  in  other  areas. 

This  alternate  way  is  actually  an  older 
technique.  Instead  of  connecting  the  modu- 
lating ac  and  the  power  supply's  dc  in  series, 
we  can  connect  them  in  paralleL  We  must 
place  a  choke  in  series  with  the  dc  power 
supply  so  that  it  won't  short  the  ac  signal  to 
ground.  The  result  looks  like  Fig.  9,  and  the 
technique  is  known  as  "Heising**  modula- 
tion. 


O 


SCO 
nui 


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^>^  BYPASS 
±    CAP 


© 


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AMP 


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B*    FROM 

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Fig.  9.  Parallef  connection  of  nnodulator  and 
modulated  stage  is  a[$o  possible.  The  circuit 
Is  known  as  "Heising"  rnodulatfon  and  has 
many  variants.  It  is  especiaMy  popular  for 
low-power  equipment  since  it  avoids  need 
for  bulky  moduiation  transformers  and  is 
capable  of  excellent  modulation  quafity. 
Disadvantage  is  that  modualtor  must  be  able 
to  dissipate  power  equal  to  that  supplied  to 
rf  stage. 

Heising  modulation  can  be  looked  at  in 
either  of  two  ways.  We'll  try  both:  To 
compare  it  to  the  picture  of  series  plate 
modulation  which  we've  just  presented,  in 
the  absence  of  modulating  signal  the  modu- 
lated  stage  gets  fuU  dc  power  from  the 
power  supply.  When  the  modulating  signal 


goes  positive,  it  adds  to  the  dc  power  and 
the  series  choke  prevents  it  from  affecting 
things  on  the  supply  side  of  the  choke,  but 
the  modulated  stage  gets  more  dc  than 
before*  Similarly,  when  the  modulating 
signal  goes  negative  it  subtracts  from  the 
power  level  on  the  modulated-stage  side  of 
the  choke,  and  the  choke  prevents  the 
supply  from  making  the  level  up.  Thus  the 
effect  on  the  modulated  stage  is  the  same  as 
with  series  modulation. 

The  other  way  of  viewing  Heising  modu- 
lation is  based  on  the  behavior  of  vacuum 
tubes.  Both  the  modulated  stage  and  the 
amplifier  producing  the  modulating  signal 
are  fed  from  the  same  power  supply, 
through  the  same  series  choke.  When  no 
modulating  signal  is  present,  both  tubes  are 
furnished  the  same  supply  voltage  and  each 
draws  the  current  determined  by  its  own 
operating  conditions. 

When  the  grid  of  the  modulating  tube 
goes  less  negative,  that  tube  draws  more 
current  The  additional  current  through  the 
choke  produces  a  voltage  drop  and  reduces 
the  voltage  available  for  both  tubes  at  the 
same  time.  This  cuts  down  the  power  avail- 
able to  the  modulated  stage  and  so  reduces 
its  output.  When  the  grid  of  the  modulating 
tube  goes  more  negative,  the  tube  draws  less 
current  The  reduced  current  through  the 
choke  releases  energy  from  the  choke's 
magnetic  field  and  raises  the  voltage  avail- 
able for  both  tubes.  The  modulating  tube 
has  no  use  for  the  increased  voltage,  so  the 
effect  is  to  raise  the  power  input  to  the 
modulated  state,  and  thus  uicrease  output. 

This  second  viewpoint  indicates  that  a 
large  part  of  the  action  of  Heising  modula- 
tion could  be  accomplished  by  using  a  large 
resistor  instead  of  the  choke  -  and  this  can 
be  done.  In  low-power  equipment  where 
both  space  and  cost  are  important^  Heising 
modulation  with  resistor  instead  of  choke 
can  be  used.  The  percentage  of  modulation 
obtained  when  this  is  done  depends  upon 
the  ratio  between  the  current  drawn  by  the 
modulating  tube  and  that  drawn  by  the 
modulated  tube.  If  the  modulating  tube 
draws  less  current,  modulation  percentage 
remains  comparativeiy  low.  If  the  modu- 
lating tube  draws  more  current  than  does  the 
modulated  stage,  though,  it's  even  possible 


96 


73  MAGAZINE 


to  overmodulate. 

Some  circuits  used  for  screen  modulation, 
incidentally,  amount  to  the  application  of 
the  Heising  technique  to  just  the  screen  of 
the  modulated  stage,  A  notable  example  is 
that  known  as  "clamp-tube*'  modulation, 
which  uses  the  Heising  technique  with  a 
resistor  rather  than  a  choke. 

Cathode  modulation,  which  is  sometimes 
employed,  is  a  cross  between  grid  and  plate 
modulation,  because  in  most  amplifiers  the 
cathode  is  common  to  both  the  grid  and  the 
plate  circuits.  It  shares  most  of  the  disadvan- 
tages of  grid  modulation  and  achieves  few  of 
the  advantages  of  plate  modulation^  and  so 
has  not  found  its  way  into  general  use- 
Now  that  weVe  looked  at  the  various 
ways  to  produce  AM  by  varying  the  ampli- 
tude characteristic  of  the  carrier,  let's  turn 
our  attention  to  FM  and  PM.  Since  the 
output  signals  produced  by  FM  and  PM  are 
so  sLmHai,  we'll  look  at  these  types  of 
modulation  together. 

We  produce  FM  by  varying  the  frequency 
of  the  carrier,  and  PM  by  varying  the  phase- 
However  it's  not  possible  to  change  the 
frequency  of  a  signal  without  at  the  same 
time  changing  its  phase^  nor  can  we  change 
the  phase  without  an  accompanying  chan^ 
of  frequency.  This  makes  the  difference 
between  FM  and  PM  largely  a  matter  of 
definition;  the  distinction  normaUy  used  is 
that  FM  can  be  applied  only  to  the  oscil- 
lator, while  PM  is  applied  to  the  signal  once 
its  center  frequency  has  been  firmly  estab- 
lished. 

The  frequency  of  any  rf  carrier  is  estab- 
lished by  a  resonant  circuit  of  some  sort  in 
the  oscillator.  This  resonant  circuit  may  be 
electromechanical,  such  as  a  quartz  crystal 
which  uses  mechanical  resonance  to  produce 
an  electrical  signal,  or  it  may  be  electronic, 
such  as  a  normal  Ic  tuned  circuit.  To  vary 
the  frequency,  we  must  vary  some  factor  in 
this  resonant  circuit 

One  of  the  most  convenient  ways,  today, 
to  produce  FM  is  to  make  use  of  the 
voltage-variable  capacitor  —  a  semiconductor 
device  which  acts  as  a  capacitor,  but  the 
capacitance  of  which  varies  with  the  applied 
voltage.  If  one  of  these  is  included  in  an  Ic 
circuit  to  provide  a  part  of  the  tuning 
capacitance,  the  modulating  signal  can  be 


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applied  to  it  to  change  the  tuning  of  the 
circuit  in  accordance  with  the  variations  of 
the  modulating  signal.  This  changes  the 
oscillator  frequency  and  produces  FM, 

The  voltage-variable  capacitor  is  a  rela- 
tively recent  device,  however,  and  a  more 
conventional  method  of  producing  FM 
makes  use  of  a  special  vacuum-tube  drcuit 
called  a  **reactance  modulator"  or  "react- 
ance tube"  to  accomplish  the  same  purpose. 


OOI 


I— I  osc 


Fig.  10.  Typical  reactance— tube  circuit  ts 
shown  here.  See  text  for  details  of  opera- 
tion. 

The  reactance  modulator  circuity  a  typical 
version  of  which  is  shown  in  Fig.  10, 
depends  upon  the  phase  relationships 
between  grid  and  plate  voltages  and  currents 
in  a  vacuum  tube.  Under  most  operating 
conditions,  the  plate  current  of  a  vacuum 
tube  is  in  phase  with  the  grid  voltage  applied 
to  that  same  tube,  without  regard  to  the 
phase  of  the  plate  voltage. 

This  means  that  we  can  place  such  a  tube 
in  a  circuit  where  ac  voltage  is  present  upon 
the  plate,  and  tap  off  some  of  this  ac  plate 
voltage.  If  we  then  shift  the  phase  of  this 
tapped  voltage  by  90^  and  feed  it  to  the 
grid,  the  plate  current  wiQ  be  90**  out  of 
phase  with  the  plate  voltage. 

Such  a  condition  defines  the  presence  of 
reactance  in  the  circuit.  If  the  current  lags 
the  voltage  by  90°,  the  reactance  is  induc- 
tive, and  if  the  current  leads  the  voltage  by 
90^,  the  reactance  is  capacitive. 

In  Fig,  10,  resistor  Rl  and  capacitor  CI 
perform  the  voltage  tapping  and  phase  shift- 
ing actions,  and  cause  the  reactance  in  the 
plate  circuit  to  be  indue tive. 

The  amount  of  reactance  present  depends 
upon  the  ratio  of  plate  voltage  to  plate 
current,  and  the  plate  current  is  determined 
by  the  tube's  transconductance  (which  is,  in 
turn,  determined  by  its  grid  voltage).  If  we 
apply  our  modulating  signal  to  the  control 
id,  through  rf  choke  RFCl  which  keeps 


the  tapped-off  plate  voltage  out  of  any 
earlier  stages  in  our  modulating-signal  chain^ 
we  can  make  it  control  the  plate  current  and 
thus  change  the  amount  of  reactance  present 
in  the  plate  circuit. 

And  that^s  exactly  what  we  do  in  the 
reactance  modulator.  The  net  effect  is  that 
we  have  a  circuit  which  acts  as  either  a 
voltage-variable  inductor  or  a  voltage^ 
variable  capacitor  (to  make  it  act  as  a 
capacitive  reactance  rather  than  inductive, 
we  simply  interchange  the  positions  of  Rl 
and  CI  to  shift  the  grid  voltage  phase  90^  in 
the  other  direction).  The  resulting  device  is 
then  connected  across  the  frequency-deter- 
mining tank  circuit  of  the  oscillator.  When 
the  reactance  tube  changes  the  reactance 
present  in  the  tank  circuit,  the  ckcuit  is 
instantly  tuned  to  some  different  fre- 
quency —  and  the  exact  frequency  to  which 
it  is  tuned  is  determined  by  the  modulating 
signal  applied  to  the  reactance-tube  input 
terminals* 

If  we  connect  a  reactance  tube,  or  a 
voltage-variable  capacitor,  to  the  frequency- 
determining  tuned  circuit  of  an  oscillator, 
we  can  produce  FM.  This  is  notj  however, 
the  only  application  of  the  reactance  tube.  If 
we  want  more  frequency  stability  than  we 
can  get  with  an  Ic  oscillator,  and  use  crystal 
control^  to  generate  the  carrier,  then  we  have 
to  xise  PM  rather  than  FM  —  and  the  react- 
ance tube  can  give  us  that,  as  well.  All  that's 
necessary  is  to  connect  it  across  a  tuned 
circuit  in  the  rf  amplifier  chain  between 
oscillator  and  antenna.  Its  reactance  varia- 
tions will  detune  the  circuit  to  which  it  is 
connected,  and  this  will  change  the  phase  of 
the  signal  to  produce  PM. 

The  reactance  tube  also  finds  application 
in  some  receiver  circuits,  to  provide  auto- 
matic frequency  control;  the  combination  of 
a  reactance  modulator  and  a  self-excited 
oscillator  is  sometimes  called  a  voltage-con- 
trolled oscillator  or  VCO,  The  VCO  is  the 
heart  of  the  advanced  receiver  technique 
known  as  ^^synchronous  detection"  or  "phase 
locked  reception*';  it*s  also  a  key  element  in 
a  TV  receiver  where  it  helps  keep  the  sweep 
signals  synchronized  with  those  of  the 
transmitter. 

Use  of  voltage-controlled  circuit  react- 
ances such  as  the  voltage-variable  capacitor 


98 


73  MAGAZINE 


or  the  reactance  tube  isn't  the  only  way  to 
achieve  either  FM  or  PM,  Any  practical 
oscillator  circuit  is,  potentially,  a  frequency 
modulator,  because  the  frequency  of  the 
signal  it  produces  is  affected  by  any  change 
in  circuit  voltages.  This  is  why  we  must 
regulate  the  voltages  applied  to  the  oscillator 
in  order  to  keep  frequency  stable.  If  we 
want  FM,  we  can  simply  reverse  things  and 
apply  any  of  the  amplitude  modulation 
techniques  to  the  oscillator  itself.  This  will 
cause  frequency  changes  which  are  deter- 
mined by  the  modulating  signaL  The  ampli- 
tude changes  which  result  can  be  wiped  out 
by  overdriving  the  following  amplifier  stages, 
so  that  only  FM  comes  out  at  the  antenna- 
We  can  produce  PM  by  doing  the  same  thing 
to  an  early  amplifier  stage,  but  it's  more 
critical. 

These  aren't  the  only  techniques  of 
achieving  FM  or  PM;  in  the  broadcast 
industry  a  special  type  of  tube  is  often  used 
which   produces    PM    almost  automatically, 

and  one  of  the  most  popular  ways  of 
achieving  broadcast  FM  is  that  invented  by 
Major  Armstrong  and  known  as  the  *' Arm- 
strong method."  It's  used  sometimes  by 
hams,  too,  who  are  set  up  for  SSB  AM 
modulation  using  the  phasing  technique  and 
want  to  produce  PM  as  welL  However,  this 
method  is  based  largely  upon  mathematical 
relationships  and  a  knowledge  of  it  isn't 
required  in  the  Extra  Class  study  questions, 
so  well  bypass  it  for  now. 

Neither  will  we  examine  the  production 
of  SSB,  DSB,  or  any  of  the  suppressed- 
carrier  modulation  techniques  at  this  point, 
since  they  are  sufficiently  complex  to 
warrant  their  own  separate  discussion  in  a 
future  installment. 

Whai  Are  The  Characteristics  Of  A  Modu- 
lated Signal?  WeVe  seen  that  modulation 
itself  consists  of  any  process  for  varying  the 
characteristics  of  a  carrier  signal  to  permit  a 
modulating  signal  to  be  transmitted,  and 
we've  looked  at  both  the  characteristics  of 
the  carrier  which  we  vary,  and  at  a  number 
of  techniques  for  varying  them.  How  about 
the  characteristics  of  the  modulated  signal, 
which  results  from  this  process? 

Like  the  carrier,  the  modulated  signal 
possesses  three  major  characteristics  —  am- 
plitude,  frequency  (or  period),  and  phase. 


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t 


t 


^ 


OCTOBER    1969 


99 


^ 


iMai 


Unlike  the  carrier,  though,  the  modulated 
signal  never  consists  of  only  a  single  fre- 
quency -  and  so  its  characteristics  are 
notably  different.  The  difference  is»  in  fact, 
what  carries  the  information! 

It's  only  logical  to  deduce  from  this  that 
the  modulated  signal's  chajacteristics  should 
be  strongly  influenced  by  the  type  of  modu- 
lation used,  and  they  are.  Because  the  type 
of  modulation  employed  has  such  an  effect 
upon  the  various  characteristics  of  the 
modulated  signal,  we'll  look  at  the  charac- 
teristics as  they  appear  with  different  types 
of  modulation  separately. 

Amplitude  modulation  is  still  the  most 
widely  used  type,  and  in  addition  we've 
considered  it  first  all  the  way  through  this 
installment,  so  we'll  examine  the  charac- 
teristics of  an  AM  signal  first  and  then  turn 
our  attention  to  FM  and  FM. 

In  our  previous  installment  we  examined 
the  how  and  why  of  mixer  action,  and 
discovered  that  when  two  signals  of  different 
frequencies  are  mixed  (as  opposed  to 
linearly  amplified)  the  result  is  not  two,  but 
four  frequencies*  The  two  original  fre- 
quencies are  still  present  in  the  output,  but 
together  with  them  are  one  new  frequency 
representing  the  difference  between  the  two 
(and  so  known  as  the  "difference"  fre- 
quency) and  another  new  frequency  which  is 
the  sum  of  the  original  pair  (called  the 
''sum"  frequency). 

The  process  of  amplitude  modulation  is  a 
mixing  process;  any  circuit  which  is  capable 
of  modulating  a  carrier  frequency  is  non* 
linear,  and  when  two  or  more  frequencies 
are  applied  to  a  non-linear  circuit,  mixing 
occurs. 

Thus  when  we  apply  our  carrier  to  an 
amplifier  stage,  and  apply  our  modulating 
signal  to  that  stage  also,  the  output  of  that 
stage  must  contain  at  least  four  frequencies 
rather  than  just  two.  If  the  modulating  signal 
is  anything  more  complex  than  a  simple 
single  sine-wave,  as  it  usually  is,  there  are 
many  more  than  four  frequencies  present  in 
the  output. 

Since  the  modulator  does  its  job  by 
mixing,  the  output  must  contain  signals  at 

each   of   the   original   input   frequencies,   at 
their  sum,  and  at  their  difference. 

Normally,  though,  a  modulator  is  used  to 


apply  audio-frequency  information  to  a 
radio-frequency  carrier.  In  this  case,  the  af 
modulating  signal  will  be  at  a  frequency  so 
far  below  that  of  the  carrier  that  no  trace  of 
the  audio  signal  itself  can  appear  in  the 
amplifier's  output  circuit;  it's  rejected  by  the 
tuned  circuits. 

The  sum  and  difference  frequencies, 
though,  are  extremely  close  in  frequency  to 
the  carrier  If  we're  modulating  a  l-mhz 
carrier  with  a  lOOhz  audio  signal,  then  the 
difference  frequency  will  be  at  999.9  khz 
and  the  sum  will  be  at  1000.1  khz.  These  are 
so  close  to  the  carrier  that  most  tuned 
circuits  which  accept  the  carrier  will  also 
accept   the  sum  and  difference  frequencies. 

Since  these  two  new  signals  lie  very  close 
to,  and  on  both  sides  of,  the  carrier,  they  are 
known  as  '*side  frequencies."  The  name 
dates  from  the  early  days  of  radio,  before  it 
was  generally  realized  that  modulation  and 
mixing  were  one  and  the  same  effect. 

When  a  band  of  many  frequencies  com- 
poses the  modulating  signal  —  the  normal 
case  with  voice  signals  —  then  the  sum  and 
difference  products  alongside  the  carrier  are 
no  longer  called  "side  frequencies";  instead, 
they  are  known  as  "side  bands."  Within  the 
past  several  years,  the  two  words  have 
blended  into  one,  and  we  know  these  parts 
of  the  modulated  signal  now  simply  as 
"sidebands." 

The  lower  sideband  corresponds  to  the 
difference  frequencies,  and  the  upper  side- 


Mh 


AUDiO 
TOIME 


i^■F 


sirtw 


CAPeiiPf 


^ 


^^. 


BAND 


LSa 


^^ 


USB 


C&ARIEI) 


Fig,  11.  Side  frequencies  are  generated  by 
mixing  or  modualtion  whenever  two  input 
signals  are  so  widely  separated  in  the  spec- 
trum as  are  af  and  rf,  Differpnce  signal  is 
lower  in  frequency  than  carrier,  and  sum 
frequency  is  higher.  When  an  audio  band, 
rather  than  a  single  spot  frequency,  is 
applied  to  mixer  or  modualtor,  output 
consists  of  carrier  and  two  sidebands.  Lower 
sideband  (LSB)  corresponds  to  difference 
frequencies,  and  upper  sideband  (USB)  to 
sums.  Total  signal  bandwidth  extends  frorn 
lowest  frequency  in  lower  sideband  to  high- 
est frequency  in  upper  srdeband,  or  twice 
the  highest  frequency  in  the  original  audio 
band. 


100 


73  MAGAZINE 


>and  to  the  sum  frequencies,  produced  by 
nixing  the  carrier  with  each  component  of 
:he  modulating  signal.  Fig,  11  shows  a  single 
pair  of  side  frequencies  (top)  and  a  typical 
set  of  sidebands  (bottom)  as  they  might  be 
/iewed  on  a  wide-range  spectrum  analyzer- 

In  passing,  we  noted  in  our  previous 
instaOment  that  mixing  action  comes 
through  a  multiplication  of  one  signal  by  the 
other  If  each  of  the  signals  applied  to  a 
modulator  (the  carrier  and  the  modulating 
signal)  are  described  by  their  equations,  the 
result  in  each  case  is  a  mathematical  expres- 
sion involving  the  sine  of  the  amount  of  time 
since  **zero  time."  If  the  two  are  multiplied, 
the  trig  relationships  involved  in  multiplying 
one  sine  function  by  another  produce  an 
equation  with  one  sine  term  and  two  cosine 
terms;  the  sine  term  turns  out  to  represent 
the  carrier,  and  the  cosine  terms  represent 
the  sum  and  the  difference  frequencies.  All 
of  this  math  was  worked  out  in  the  mid- 
1920*s-but  at  the  time  the  "side  fre- 
quencies*' and  resulting  sidebands  were 
thought  to  be  a  mathematical  fiction.  The 
experts  felt  that  they  couldn't  possibly 
exist,  but  they  were  necessary  to  make  the 
math  work  out  properly. 

Then  in  1927  John  Carson  demonstrated 
the  physical  existence  of  the  sidebands^  and 
took  out  a  patent  on  a  system  of  single 
sideband  transmission*  The  math  was  vindi- 
cated; unfortunately,  it*s  still  not  an 
accurate  picture  of  what  goes  on,  because 
the  mathematical  expression  fails  to  account 
for  the  original  modulating  signal. 

Much  later  it  was  realized  that  modula- 
tion and  mixing  are  two  names  for  the  same 
process  (at  least  so  far  as  AM  is  concerned), 
and  the  body  of  theory  developed  to 
describe  mixer  action  was  applied.  Many 
college-level  engineering  texts  still,  however, 
teach   modulation    without    going   into   its 

connection  with  mixing. 

The  references  generally  available  to  most 

hams,  though,  are  even  less  cle^,  because 

many  of  them  leave  the  impression  that  the 

amplitude  of  the  carrier  is  varied  to  produce 

amplitude  modulation. 

In  fact,  we've  even  implied  as  much 
ourselves  —  and  its  time  to  correct  that  idea. 

We  saw  just  a  few  paragraphs  back  that 
the  sidebands  lie  very  close  indeed  to  the 


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I 


OCTOBER    1969 


101 


carrier  in  the  frequency  spectram.  For  all 
practical  purposes,  the  two  sidebands  and 
the  carrier  together  constitute  a  single  signal, 
because  most  receivers  are  not  sufficiently 
selective  to  strip  out  any  part  of  this 
combination  from  the  rest  of  it. 

But  when  this  composite  signal  is  applied 
to  any  electronic  circuit,  there's  only  so 
much  energy  present  in  that  circuit  at  any 
specific  instant.  That  is,  the  energy  present 
in  the  circuit  is  the  net  total  of  that 
contributed  by  the  lower  sideband,  the 
carrier,  and  the  upper  sideband ,  all  at  the 
same  time.  If  the  energy  in  the  sidebands  is 
of  just  the  right  amount  and  polarity  to 
completely  cancel  the  energy  of  the  carrier, 
this  net  total  will  be  zero,  and  on  the  other 
hand  if  the  same  amount  is  contributed  but 
with  polarity  to  boost  rather  than  buck  the 
carrier  level,  the  total  will  be  twice  as  much 
energy  or  four  timw  as  much  power  as  with 
the  carrier  alone. 

The  variations  of  net  energy  in  the  total 
signal  produced  by  the  amplitude  and 
polarity  changes  of  the  sidebands  relative  to 
the  carrier  are  called  the  *" modulation 
envelope^'  or  simply  the  "envelope"  of  the 
signal  —  and  in  amplitude  modulation  it*s 
the  amplitude  of  the  envelope  rather  than 
that  of  the  carrier  which  varies. 

The  distinction  is  more  theoretical  than 
practical,  because  as  we  said,  it's  almost 
impossible  to  separate  parts  of  the  com- 
posite out  with  most  receivers,  A  "selectable 
sideband"  receiver,  though,  has  the  ability  to 
accept  or  reject  a  single  sideband  of  an  AM 
signal,  and  the  whole  art  of  SSB  is  based  on 
the  fact  that  all  the  modulation  information 
is  contained  in  the  sidebands,  and  that  the 
sidebands  are  mirror  images  of  each  other  so 
that  only  one  is  necessary  to  carry  all  the 
information. 

Fig,  12  shows  the  envelope  of  an  AM 
signal  over  a  half-cycle  of  modulating  signal* 
This  is  not  typical  since  only  a  3-to-l  ratio 
between  carrier  and  modulating  frequencies 
was  used  J  in  order  to  permit  easy  vision  of 
the  relationships  between  net  energy  in  the 
composite  signal  (dotted  Une)  and  the 
envelope  (sohd).  Normally  the  frequency 
ratio  is  much  higher.  Like  all  the  other 
waveform  illustrations  in  this  installment, 
this  figure  was  traced  from  a  plot  produced 


Fig,  12,  Envelope  of  AM  corresponds  to  the 
peaks  of  the  energy  levels  present  in  the 
connbined  carrier  and  both  sidebands  (dot- 
ted waveform).  This  iUustration  shows  a  full 
cycle  of  modulating  signal  from  negative 
peak  to  the  next  negative  peak^  with  six 
cycles  of  carrier/sideband. 


by  an  electronic  computer.  i 

The  relationship  in  strength  between 
either  sideband  and  the  carrier  is  a  measure 
of  an  AM  modulation  system's  effectiveness. 
The  stronger  the  sideband,  as  compared  to 
the  carrier,  the  more  effective  the  system. 

This  relationship  is  usually  expressed  by 
engineers  as  the  "modulation  index"  of  the 
modulated  signal,  but  hams  and  the  FCC 
refer  to  it  in  a  slightly  different  form  caUed 
the  "percentage  of  modulation/'  This^  again, 
is  a  carryover  from  the  days  when  only  the 
envelope  was  considered  -  and  as  a  result 
the  definitions  of  modulation  percentage 
make  very  little  sense  when  applied  to  a 
suppressed-carrier  signal,  and  none  at  all 
when  applied  to  FM  or  PM. 

For  "percentage  of  modulation"  is  deter- 
mined by  the  ratio  of  peak  envelope  voltage 
(or  current)  to  the  carrier  voltage  (or  cur- 
rent) without  modulation.  Fig,  12  shows 
these  parts  of  the  envelope.  The  carrier  level 
is  indicated  by  the  dotted  line. 

Percentage  of  modulation  may  be  dif- 
ferent for  "upward  modulation,"  which  is 
the  half-cycle  of  the  modulating  signal  which 
produces  the  positive  modulation  peak,  than 
for  "downward  modulation"  which  pro- 
duces the  negative  modulation  peak.  For 
sine- wave  modulation  both  are  the  same,  but 
for  voice  the  two  are  normally  different  The 
larger  of  the  two  figures  is  customarily  used 
as  the  modulation  percentage  of  the  signal. 

In  the  case  of  upward  modulation,  the 
modulation  percentage  is  100  times  the  ratio 
of  the  positive  modulation  peak  (above 
carrier  level,  as  shown)  to  the  carrier  level.  In 
Fig.  12,  both  are  equal  and  the  ratio  is  1/1, 
so  the  modulation  percentage  upward  is 
100%, 


102 


73  MAGAZINE 


CAf?RiER 
LEVEL 


F1g>  13.  Key  factors  invofvad  In  calculdtlng 
percentage  of  modulation  are  identified 
here.  Wave  form  repre^nts  tOO%  modulated 
enverope  (carrier  cycles  are  not  shown)  as 
described  in  text.  Carrier  level  furnishes  zero 
reference  for  envelope;  envelope's  outline 
dupficates  modulating  signal  on  both  edges* 

For  downward  modulation,  the  per- 
centage is  100  times  the  ratio  of  the  negative 
modulation  peak  (below  carrier  level)  to  the 
carrier  level.  In  Fig.  12,  again  both  are  equal 
so  the  ratio  is  1/1,  making  the  percentage 
again  equal  to  1 00%, 

FCC  regulations  limit  modulation  per- 
centage of  an  AM  signal  to  100%  in  either 
direction.  There's  very  good  reason  for  this 
in  the  downward  direction;  100%  modu* 
lation  justs  cuts  off  the  envelope  at  zero 
energy.  Anything  in  excess  of  100%  modu- 
lation represents  an  effort  to  make  the 
envelope  less  than  zero;  it  doesn't  work. 
What  happens  is  that  the  negative  modula- 
tion peaks  are  highly  distorted,  and  this 
distortion  produces  spurious  signals  which 
clobber  communications  over  a  wide  spread 
of  the  frequency  spectrum.  See  Fig.  13. 

Modulation  percentage  is  relatively  inap- 
plicable to  SSB  or  DSB,  since  these  signals 
have  no  '"carrier  level''  to  m^isure  against 
We'll  find  out  why  it*s  not  applicable  at  all 
to  FM  or  PM  a  little  later. 

When  you  understand  how  modulation 
percentage  is  defined,  it*s  not  too  difficult  to 
visualize  the  envelope  of  a  sine-wave-modu- 
lated  signal  at  any  prescribed  percentage  of 
modulation.  Simply  establish  a  carrier  with  a 
peak  voltage  of,  say»  10,  and  then  sketch  in 
the  modiilating  sine-wave  along  the  carrier 
level  Positive  peaks  of  the  modulation 
envelope  will  rise  above  carrier  level  by  the 
modulation  percentage  times  the  carrier 
level;  that  is,  with  a  10-volt  carrier  and  50% 
modulation,  positive  peaks  wiU  rise  to  IS 
volts.  Negative  peaks  will  drop  below  carrier 


OCTOBER    1969 


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level  by  the  same  amount;  m  our  example, 
to  10-5  or  5  volts. 

If  the  percentage  exceeds  100%,  positive 
peaks  still  go  up  in  the  same  way,  but 
negative  peaks  cut  off  at  the  carrier  zero 
reference  line  to  produce  a  distorted 
envelope. 

We  have  seen  how  all  of  the  information 
content  of  the  envelope  is  produced  by  the 
sidebands,  in  AM,  We  have  also  seen  how  the 
sideband  energy  levels  produce  the  envelope 
of  the  signal.  It  shouldn't  be  too  surprising 
to  learn  that  all  of  the  power  furnished  by 
the  modulating  signal  goes  into  the  side- 
bands. 

Strictly  speaking,  that's  true  only  of  plate 
modulation,  because  that's  the  only  type  of 
modulation  we\e  examined  in  which  the 
input  powef  is  varied  to  produce  modula- 
tion. But  with  plate  modulation,  that  is  what 
happens.  The  amplifier  treats  the  carrier  the 

same  at  all  times,  whether  modulation  is 
present  or  absent  When  modulation  is 
applied,  the  modulating-signal  power  pro- 
duces the  sidebands. 

We  adso  saw  that  100%  modulation  is 
produced  when  the  sidebands  have  just  the 
right  amount  of  energy  to  completely  cancel 
out  the  carrier  energy  at  the  negative  modu- 
lation peaks.  Because  of  some  rather  com- 
plicated phase  relationships^  this  occurs 
when  each  of  the  two  sidebands  has  pe^ 
voltage  equal  to  half  that  of  the  carrier. 
Then  tiie  two  sidebands  each  contribute 
half,  and  the  total  exactly  balances  out  the 
canier. 

With  half  the  voltage  in  each  sideband, 
tlm  means  that  each  sideband  must  contain 
1/4  as  much  average  power  as  does  the 
carrier  m  order  to  attain  100%  modulation 
with  a  sine-wave  signal.  To  put  1/4-carrier- 
power  levels  into  each  of  two  sidebands 
requires  that  the  modulator  supply  pow^ 
equal  to  half  that  in  the  carrier. 

Should  we  reduce  the  modulation  per- 
centage, the  amount  of  power  required  in 
the  sidebands  would  also  be  reduced.  Should 
we  use  something  other  than  a  sine  wave  as  a 
modulating  signal,  as  for  example  normal 
speech,  we  could  also  get  by  with  less  power. 
As  a  rule  of  thumb,  though^  most  designers 
try  to  furnish  half  as  much  audio  power  as 
there  is  gQing  to  be  rf  power  in  the  carrier. 


This  offers  a  safety  margin,  and  also  permits 
speech  processing  such  as  clipping  and  com- 
pression without  running  short  of  modu- 
lating power. 

Because  the  carrier  level  remains  constant 
with  plate  modulation,  which  is  the  most 
popular  kind,  many  people  believe  that 
carrier  level  is  always  constant  with  modula- 
tion. This  is  not  necessarily  so. 

When  AM  is  achieved  by  varying  effi- 
ciency of  an  amplifier,  as  is  done  in  all  types 
of  grid  modulation,  it's  simply  the  designer's 
choice  as  to  whether  carrier  remains  con- 
stant, or  varies  with  modulation.  Many 
designers  of  such  systems  have  attempted  to 
produce  output  indistinguishable  from  that 
produced  by  plate  modulation  —  and  in 
these  systems,  carrier  remains  constant. 

Other  designers,  though,  have  chosen  to 
control  the  carrier  level  AH  controUed- 
carrier  systems  (a  notable  example  is  a 
Heathkit  design  originally  introduced  about 
1955  and  still  cuiient)  produce  carrier  levels 
which  vary  with  the  intensity  of  the  modu- 
lating signal. 

Even  in  these,  though,  the  ratio  of  power 
between  carrier  and  sidebands  remains  fixed 
by  the  modulation  percentage. 

Now  that  weVe  given  AM  signal  charac- 
teristics a  thorough  going-over,  let*s  see  how 
FM  and  PM  differ 

For  a  starter,  the  envelope  of  an  FM 
signal  carries  no  information.  In  fact,  a  legal 
FM  or  PM  signal  has  no  envelope  variations 
at  all,  because  that  would  constitute  AM  and 
the  rules  don*t  permit  mixing  the  types. 

FM  and  PM  signals  do,  however,  have 

m 

si#bftn4s  —  many  more  sidebands  than  are 
pro4uced  by  AM  at  the  same  modulation 
index.  Moft  texts  drop  into  a  deep  and 
somewhat  muiky  study  of  Bessel  functions 
when  they  attempt  to  discuss  the  distribu- 
tion of  $ideb»nds  in  FM  signals.  Since  we 
don't,  at  this  point,  need  all  that  infoi^ 
mation,  let's  9kip  the  details  of  how  they  are 
produced  and  simply  note  that  the  visualiza- 
tion most  of  us  cany  of  an  FM  signal  -  a 
aingile  carrier  which  wande^^  about  in  Ire* 

qu^liqy  around  a  "center*'  frequency,  and 
whose  wan4«ruigs  carry  the  modulating 
signal  information  -  is  np  more  accurate  in 
detail  than  19  the  conventional  view  of  an 
AM  signal  as  one  whose  strength  varies  with 


104 


73  MAGAZINE 


modulation.  See  Fig.  14. 

In  both  cases,  it's  the  envelope  charac- 
teristics which  vary  rather  than  those  of  any 
specific  components  within  the  signal. 

This  comes  about  because  a  signal  of  any 
one  frequency  cannot  be  at  any  other 
frequency  —  and  it  can't  get  from  one  fre- 
quency to  another  without  getting  to  one  in 
between  first.  When  it*s  necessary  to  analyze 
in  detail  how  a  modulation  system  works, 
it*s  more  convenient  to  view  the  si^al  as 
being  made  up  of  many  signals  each  of 
specific  frequency  and  strength^  which  are 
either  present  or  absent^  than  it  is  to  try  to 
consider  one  signal  of  varying  frequency  or 
strength. 

Since  the  advent  of  SSB^  it's  become 
necessary  to  examine  AM  in  this  amount  of 
detail.  When  looking  at  FM,  we  can  get  by 
with  studying  only  the  behavior  of  the 
envelope;  we  don't  have  to  break  down  the 
various  components  within  the  envelope. 

The  FM  signal  is  characterized  by  its 
center  frequency,  strength,  and  the  amount 
of  deviation  above  and  below  this  center 
frequency.  The  deviation  may  be  expressed 
either  as  an  absolute  frequency  difference  in 
hertz  or  khz,  in  which  case  it's  called 
"swing/'  or  as  the  "deviation  ratio,"  which 
is  the  ratio  of  the  maximum  carrier-fre- 
quency deviation  to  the  highest  nlodulating 
frequency.  The  effectiveness  of  the  modula- 
tion is  measured  by  the  *' modulation  index," 
which  is  the  ratio  of  the  carrier  frequency 
deviation  to  the  modulating  frequency.  That 
is,  a  3-kliz  swing*  with  a  l-khz  modulating 
frequency  would  produce  a  modulation 
index  of  3;  the  same  swing  with  a  6-khz 
modulating  frequency  would  produce  a 
modulation  index  of  O.S,  and  if  the  34c hz 
swing  were  the  maximum  employed  in  the 
system,  and  the  64:hz  signal  the  highest 
frequency^  then  the  deviation  ratio  would 
also  be  0.5. 

In  ham  use  below  52,5  mhz,  the  maxi- 
mum bandwidth  which  an  FM  signal  is 
permitted  is  6  khz  (the  same  as  a  state-of- 
the-art  AM  signal).  If  frequency  response  is 
limited  to  3  khz,  then  the  deviation  ratio 
would  be  2;  the  modulation  index  would 
vary  with  the  modulating  frequency,  from  2 
at  the  high-frequency  limit  up  to  20  at  a 
300-hz  modulating  signal 


Fi(|.  14.  This  composite  view  shows  an  FM 
signal's  waveform  (solid  line),  compared  to 
that  of  an  unmodulated  carrier  of  the  same 
center  frequency  {dotted}  and  to  the  modu- 
lating sine- wave  (also  dotted)^  Sine-wave 
shape  of  carrier  and  modulated-signat  wave- 
forms has  bean  simplified  to  straight  line 
connecting  peaks  and  passing  through  a^is 
at  proper  zero-crossing  time. 

In  AM,  modulation  index  is  the  ratio  of 
modulation  peak  level  to  average  carrier 
level  —  the  same  quantity  which  we  multiply 
by  100  to  obtain  modulation  percentage.  A 
100%  modulated  AM  signal  has  a  modula- 
tion index  of  1,0,  Modulation  percentage  is 
sometimes  defined^  in  fact,  as  100  times  the 
modulation  index. 

This  is  part  of  why  modulation  per- 
centage has  no  meaning  in  FM  work.  Modu- 
lation peaks  are  always  at  the  same  level  as 
the  average  carrier  level,  and  by  conventional 
definitions  aU  FM  has  0%  modulation.  But  if 
100  times  modulation  index  is  used,  then 
the  modulation  percentage  of  a  legal  ham 
FM  signal  may  vary  from  200  up  to  2000%, 
depending  upon  modulation  frequencies 
present 

In  practice^  the  deviation  ratio  is  used  to 
measure  FM  in  the  same  way  modulation 
p^centage  is  used  for  AM. 

But  while  it*s  possible,  physically,  to 
overmodulate  an  AM  signal  and  produce 
splatter,  this  cannot  be  done  with  FM.  An 
FM  signal  with  more  swing  than  a  receiver  is 
designed  to  accomodate  will  sound  distorted 
on  that  receiver  -  but  will  be  fine  on  any 
receiver  which  can  handle  the  maximum 
swing  of  the  signal.  The  limits  on  swing  of  an 
FM  signal  are  administrative,  while  those 
upon  modulation  percentage  of  AM  are 
physical.  ...  73  Staff 


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month,  and  earn  a  very  good  commission. 
Send  your  credentials  to  Instant  Gourmet 
Peterborough,  N.H,  03458. 


I 


1 


I 


OCTOBER    1969 


105 


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73  Magazine 

Peterborough.  N.  H.  03458 


OCTOBER    1969 


107 


■^1^^ 


Ed  Gribi  VJB61ZF 
229  Vivian  Street 
King  City,  CA 


Hi 


am 


Jamboree 


Editor  Wayne  waxed  eloquently  in  July 
73  about  the  need  for  attracting  newcomers 
into  our  hobby.  One  of  the  largest  groups  of 
ready*made  potential  newcomers  are  the  ten 
million  or  so  Boy  Scouts  around  the  world. 
There  are  a  number  of  points  of  contact 
between  scouting  and  amateur  radio,  but 
one  of  the  best  is  the  annual  "Jamboree  On 
The  Air," 

What  is  Jamboree  Or^The  Air?  Let  me  try 
to  describe  its  background,  purposes,  and 
format  for  you  from  a  very  personal  stand- 
point, I  had  the  good  fortune  to  be  one  of 
the  operators  at  K7WSJ,  the  official  amateur 
station  at  the  World  Scout  Jamboree  at 
Farragut  State  Park,  Idaho,  in  August^  1967, 
Those  ten  days  were  one  of  the  high  points 
of  my  43  years.  Meeting  Lady  Powell,  the 
night  the  entire  Australian  contingent  jam- 
mod  our  shack  as  we  worked  VK  after  VK 
(no  third  party  traffic,  please!);  the  colors  of 
the  tents  and  banners  against  the  green 
Idaho  forest;  the  Belgian  Scout  who  brought 
his  sleeping  bag  into  the  shack  in  the  hope 
we  could  work  an  ON;  the  myriad  of 
colorful  uniforms  and  thousands  of  smiling 
faces  thoroughly  enjoying  one  of  the  great 
experiences  of  their  Mves,  These  and  hun- 
dreds of  other  thrills  and  pleasant  memories 
will  always  be  with  me.  1  made  many  lasting 
friendships  from  a  dozen  different  countries 
and  still  exchange  letters  with  several  of 
them.  But  I  was  one  of  the  lucky  ones. 
Fewer  than  1%  of  the  Scouts  are  able  to 
attend  a  World  Jamboree  or  one  of  the 
greatest  national  or  regional  jamborees. 
Therein  hes  the  reason  for  the  development 
of  Jamboree  On  The  Air, 


Scouts  at  Geneva,  Switzerland,  Operator  is 
Len  Jarrett,  HB9AMS,  Director  of  Adminis- 
tration, Boy  Scouts  World  Bureau^ 

A  number  of  Scouts  operating  the  ama- 
teur station  during  the  World  Jamboree  in 
England  in  1957  were  concerned  that  so  few 
Scouts  of  the  millions  could  actually  partici- 
pate in  the  face  to  face  building  of  interna- 
tional friendships.  Perhaps  radio  could  ex- 
tend the  reach  of  the  brotherhood  and 
involve  more  Scouts,  even  if  vicariously,  in 
such  events,  Les  Mitchell,  G3BHK,  con- 
ceived the  idea  of  a  Jamboree  on  the  air  and 
the  first  formal  JOTA  was  in  May^  1958, 
The  idea  has  mushroomed  with  the  aid  and 
abettment  of  enthusiastic  Scouts,  Scouters, 
and    amateurs    so    that    now    thousands   of 


108 


73  MAGAZINE 


stations  from  every  Scouting  country  parti- 
cipate in  the  event  every  year. 

The  primary  purpose  of  J  OTA,  therefore, 
is  to  enable  Scouts  everywhere  to  talk  to 
other  Scouts  across  town  or  around  the 
globe  by  radio,  A  secondary  purpose  is  to 
give  them  exposure  to  amateur  radio  which 
may  help  a  boy  discover  a  latent  career  in 
electronics  or  some  allied  field ,  or  perhaps  in 
amateur  radio  as  a  hobby.  It  has  undoubted- 
ly encouraged  many  a  boy  to  work  on 
related  Scouting  accomphshments  such  as 
radio  and  other  merit  badges. 

The  12th  annual  Jamboree  On  The  Air 
will  occur  October  18  and  19,  (GMT),  1969. 
Participating  stations  with  Scouts  and  Scout- 
ers  in  their  shacks  will  be  calling  **CQ 
Jamboree**  on  aU  bands  and  modes  during 
that  period.  There  are  no  rules  nor  points  to 
count  "-tills  is  not  a  contest!  The  theme  is  to 
let  Scouts  talk  to  Scouts  wherever  they  may 
be.  There  are  no  formal  fixed  frequencies, 
but  the  Boy  Scouts  World  Bureau  has 
recognized  traditional  operating  practices  by 
noting  the  following  as  ''World  Scout  Fre- 
quencies": 

3,590  khz.  -CW 
3,740  khz,  —  European  phone, 

U.  S.  Novice  CW 
3,940  khz,  -  U,  S.  phone 
7,090  khz,  —  CW,  European  phone 

14,090  kliz,  --  CW 

14,290  khz.  —  phone 

21,140  khz.  -  CW,  U.  S.  Novice 

21,360  khz.  -  phone 

28,190  khz,  -  CW 

28,990  khz,  -phone 
In  addition,  U.  S.  amateurs  have  found  7290 
khz  to  be  a  good  frequency  and  7190  khz  a 
good  CW  frequency  for  novices. 

If  you,  as  an  amateur  and/or  Scout  or 
Scouter  are  not  already  involved,  then  per- 
haps this  should  be  your  year  for  Boy 
Scouts,  You  might  contact  a  local  Scout 
office  or  executive  or,  even  better,  a  Scout- 
master or  Den  Mother  or  Patrol  Leader. 
They  may  not  be  familiar  with  the  event 
unless  they  are  avid  readers  of  "Scouting," 
"Boys  Life,*'  or  **World  Scouting."  You  may 
have  to  explain  the  purposes  and  what  they 
might  reasonable  expect  from  participation 
(remeniber,  though,  that  propagation  may 
not  cooperate).  In  many  areas  amateurs  talk 


to  Scout  Troops  several  weeks  before  the 
event  to  explain  such  things  as  how  we're 
able  to  communicate  hundreds  or  thousands 
of  miles,  typical  terminology  involving 
equipment  and  operatmg,  and  perhaps  even 
to  arrange  a  preliminary  visit  to  a  station. 

During  the  event  get  your  amateur  opera- 
ting exchanges  out  of  the  way  as  briefly  as 
possible.  Then  turn  the  boys  loose  and  let 

them  talk  to  other  Scouts.  If  they're  a  little 
totigue-tied  at  first,  encourage  them  to  talk 

about  such  things  as  themselves  and  their 
own  personal  involvement  in  Scouting;  tlieir 
Patrol,  Troop,  Post,  or  Den;  their  camping 
and  other  activities;  their  home,  town,  area^ 
and  its  culture  and  environment;  and,  of 
course,  to  ask  similar  questions  of  those  on 
the  other  end,  DonH  feel  like  you  have  to 
hurry  off  to  make  more  contacts  or  to  let 
them  talk  to  some  exotic  DX  Scout  station. 
It  is  much  more  meaningful  and  closer  to  the 
purposes  of  the  event  to  have  a  two-hour 
ragchew  with  a  gang  100  miles  away  than  it 
is  to  exchange  signal  reports  with  stations  in 
ten  countries.  I've  hstened  in  on  some 
marvelous  QSO's  during  past  events  where, 
for  instance,  a  couple  of  Patrol  Leaders  in 
different  parts  of  the  USA  exchanged  notes 
on  their  summer  camp  experiences  or  Ten- 
derfeet  talked  about  their  first  hike.  On  the 
other  hand,  if  conditions  are  favorable  it  can 
be  a  real  thrill  for  them  to  talk  "live"  to  a 
Scout  in  some  foreign  country.  The  language 
barrier  is  no  barrier  when  international 
friendsliip  is  involved. 

When  it's  all  over  the  very  least  you'll 
have  is  a  lot  of  satisfaction  in  having 
associated  with  a  fine  group  of  young  men,  I 
know  it  always  restores  my  faith  in  the  basic 
good  sense  of  our  youth  whenever  1  get 
around  a  group  of  Scouts,  Beyond  that  there 
are  several  things  that  can  be  done  that  will 
extend  the  interest  period  and  firm  up  the 
relationships  begun.  Encourage  the  Scouts  to 
make  up  and  send  QSL  cards  to  the  groups 
they  talk  to  and  perhaps  to  initiate  corres- 
pondence or  exchange  of  photos.  Many 
permanent  overseas  links  between  Scouting 
groups  have  begun  this  way.  And  by  ail 
means  send  a  note  regarding  your  JOTA 
activities  (including  contacts  and  critique)  to 
your  National  Organizer  (in  the  United 
States    it's    Harry    Harchar   W2GND,    Boy 


I 


OCTOBER    1969 


109 


Scouts  of  America,  New  Brunswick,  New 
Jersey-  08903)  with  a  copy  to  the  World 
Organizer^  Len  Jarrett  HB9AMS,  Boy  Scouts 
World  Bureau,  Case  Postale  280,  1211  Gene- 
va 11,  Switzerland,  Len  is  an  enthusiastic 
participant  in  JOTA's  and    will  again  this 

year  be  operating  from  4UIITU  until  a 
permanent  World  Bureau  station  can  be  set 
up.  World  Scout  Bureau  will  send  you  a 
handsome  QSL-sized  ceritficate  of  participa- 
tion in  return  for  your  courtesy  in  telling 
them  of  your  own  activities. 

So  youVe  done  all  these  things  but  it  stiU 
seems  like  the  contact  between  amateur 
radio  and  Scouting- should  be  more  than  a 
once-a-yeai  thing,  I  always  have  that  feeling 
myself.  There's  no  reason  why  you  couldn't 
continue  the  relation  with  a  particular 
Scouting  group  with  such  diverse  projects  as 

teaching  them  code,  providing  communica- 
tions at  a  Camporee  or  camp,  or  maintaining 
schedules  with  someone  contacted  during 
JOTA.  There  are  several  nets  devoted  to 
Scouting  in  various  portions  of  the  world, 
G3BHZ  and  HV3SJ  operate  on  14290  khz 
on  Saturdays  at  0930  GMT,  mostly  with 
other  European  participants.  World  Scout 
Net  operates  on  21360  khz  at  1800  GMT  on 
Saturdays.  Bob  Hallock  WA7G00,  is  the 
prime  mover  in  this  group.  Bob  was  an 
operator  at  K7WSJ  in  1967  and  at  the 
National  Jamboree  station  this  last  July,  Bob 
is  an  Eagle  Scout  from  Boise,  Idaho,  and  has 
injected  a  lot  of  enthusiasm  into  the  WSN. 
These  gBOUps  are  devoted  to  the  furtherance 
of  the  ideals  of  Scouting  via  amateur  radio 
and  as  such  deserve  support  and  participa- 
tion by  aH  with  similar  aims. 

I  have   one  suggestion   regarding  JOT  A 


Australian    Scouts 

1968  JOTA. 


at    VK2BW    during    the 


At    Baden   Powell    House,    London— English 
Scout  headquarters. 

Operation  this  year  that  I  haven't  even 
cleared  with  Len  Jarrett  at  the  World  Bur- 
eau, Let*s  try  using  these  World  Scout 
Frequencies  as  calling  frequencies  during 
JOTA  instead  of  ragchew  frequencies*  In 
other  words  J  call  "CQ  Jamboree"  on  the 
frequency,  then  QSY  up  or  down  for  a  QSO. 
That  way  there  would  be  much  more  effi- 
cient utiltization  of  frequency  space  and 
much  less  random  calling.  Perhaps  we  could 
even  have  net  control  stations  active  on  one 
or  more  of  the  frequencies,  particularly 
21,360  khz.  I  imagine  Bob  WA7G00,  could 
organize  two  or  tliree  net  controls  to  pick  up 
breaks,  periodically  call  a  list  of  stations  and 
localities  on  the  frequency,  and  help  stations 
who  wish  to  QSY  for  a  chat.  Til  see  if 
something 4ike  this  might  be  arranged  by  the 
time  this  appears  in  print.  During  other 
times  these  frequencies  should  make  natural 
frequencies  for  any  stations  interested  in 
Scouting  to  get  together. 

So  there  you  have  the  story  of  Jamboree 
On  The  Air*  If  youVe  interested  in  young 
people  and  in  the  health  of  amateur  radio, 
this  should  be  a  regular  event  for  you.  If  you 
feel  as  I  do  that  once  a  year  just  whets  your 
appetite,  then  you  might  follow  some  of 
these  other  suggestions  that  could  lead  to  a 
Jamboree  On  The  Air  tlie  year  round. 

r*  x^  •  .  .  WBoIZF 

Reference: 

"Scouting  and  the  Radio  Amateur/*  QST,  July, 
1967,  p,52,  WB6IZF 


110 


73  MAGAZINE 


NEW   PRODUCTS 

Two  Meter  Transceiver 

f  J  any  amateurs,  tired  of  using  older  taxi 
ana  police  FM  equipment,  have  been  looking 
for  reasonably  priced  new  equipment  to 
come  on  the  market,  Varitronics  has  just 
announced  a  new  solid  state  FM  transceiver 
designed  and  priced  for  the  amateur  market. 
It  has  six  crystal  controlled  channels  and 
runs  from  12-15  vdc.  The  power  is  10  watts 
input.  The  unit  is  built  with  sub-printed 
circuit  boards  of  the  computer  module  type^ 
making  the  unit  small  enough  for  easy 
portable  and  mobile  use< 


Varitronics  also  has  a  one  watt  output 
unit  available  which  can  work  with  a  battery 
pack,    a    six    meter   crystal   controlled   FM 

transceiver  and  a  dual  vfo  six  meter  AM-FM 
transceiver.  Write  to  Varitronics^  3835  North 
32nd  Street,  Suite  6,  Phoenix,  AZ  85018. 

More  Power  for  FM'ers 

Varitronics  Inc.  has  come  out  with  two 
new  linear  amplifiers  for  users  of  their 
deluxe  FDFM-2  transceiver. 

For  the  mobile  enthusiasts,  the  com- 
pletely solid  state  FM-20M  mobile  rf  linear 
amplifier  can  be  had  for  $150.00,  weighs  but 
a  pound,  requires  12*5  vdc  and  can  boost 
your  nere  2  watts  to  20  watts  input  and  10 
watts  rf  output.  For  those  using  the  FDFM-2 
transceiver  as  a  home  station,  you  might 
look  into  the  new  FM-2OBM5  available  for 
$235.00.  It  weighs  6V2  pounds,  is  completely 
solid  state^  has  a  built-in  ac  power  supply 


requiring  117  vac,  and  like  the  FM-20M 
mobile  model,  can  increase  2  watts  input  to 
20.  For  further  in  forma  tion,  write  Vari- 
tronics Inc.,  3835  North  32nd  Street,  Suite 
6,  Phoenix,  Arizona  85018. 


,.+rtl^'  '^  vr  «    i^-r 


r  M  ^  4\wir   -  ^*_4r  ^#  ^  ^>  ^   « 


A  ^  4  J  .# 


Now  the  HA^SOO 

Lafayette  introduces  the  new  completely 
solid-state,  model  HA-800  six-band  SSB/ 
AM/CW  amateur  receiver.  This  80-6  meter 
amateur  receiver  has  a  built  in  dual  solid 
state  power  supply  permitting  either  117 
volts  ac  or  12  volt  dc  operation  with  zener 
regulation.  The  receiver  section  sports  3 
FET's  and  2  mechanical  if  filters  to  assure 
high  selectivity  with  superior  noise  suppres- 
sion* An  S  meter,  product  detector  and 
crystal  calibrator  (less  crystal)  are  among  the 
other  features.  Specifications:  sensitivity: 
better  than  1  uv  on  80,  40,  20  meters,  ,5  uv 
on  15,  10  meters  and  2,5  uv  on  6  meters; 
selectivity:  -6db  at  ±2  khz,  -60db  at  ±6  khz; 
intermediate  frequencies!  1st  if  2.608  mhz, 
2nd  ?/  455  khz;  BFO  frequency:  455  khz 
±2-5  khz;  image  rejection:  better  than  -40db; 
audio  output  impedance:  50  ohms;  power 
requirements  105-120  volts  50/50  hz  ac,  12 
volts  dc  (negative  ground);  size:  15w  x  9%d 
X  8!4h.  For  additional  information,  write 
Lafayette  Radio  Electronics  Corp.,  Ill 
Jericho  Turnpike,  Syosset,  L.L,  NY  11791. 


FMT-1   FIVI  Transceiver 

VHF  Associates,  Inc.,  is  now  offering  a 
six  channel,  5  watt  input  FM  transceiver  for 
$289.95,  It  operates  with  a  dc  input  voltage 
of  1 2  to  15  volts  and  weighs  but  six  pounds, 
being  fully  transistorized.  ICs  are  used  in 
the  if  and  audio  circuits  for  superior  perfor- 


OCTOBER    1969 


111 


mance  and  reliability  and  the  receiver  is  dual 
conversion.  The  transmitter  has  a  20  khz 
maximum  deviation  and  has  a  frequency 
range  of  142  to  149  mhz.  For  further 
information,  write  VHF  Associates,  Inc.,  PO 
Box  22135,  Denver,  CO  80222, 

Arcturus 

Arctunis  Electronics  Corp.  has  been  lucky 
enough  to  acquire  9800  obsolete  tubes,  circa 
1925-1930,  to  add  to  their  considerable  in- 
ventory of  the  same  hard-to-obtain  types. 
Listings  plus  prices  of  thousands  of  other 
items  are  included  in  their  recently  published 
Mid- 1969  Catalog,  which  they  will  be  glad  to 
send  to  you  without  any  obligation  on  your 
part.  Write  direct  to  Arcturus,  505-22nd  St., 
Union  City,  N J.  07087. 


Cassette  Albums  Available 

Now  that  more  and  more  of  us  are  using 
cassette  tape  recorders  to  tape  our  friends 
and  unusual  DX  contacts,  the  problem  of 
storing  those  little  cartridges  begins  to  in- 
trude. They  are  a  terrible  size  to  store  and 
they  soon  rattle  around  in  the  desk  drawer. 
Robins  Industries,  College  Point,  N.Y. 
11356,  has  come  out  with  a  nice  album. 
Each  cover  holds  six  cassettes  and  each 
compartment  has  a  built-in  stop  to  keep  the 
tape  from  going  slack!  The  cost  is  $3.30 
each.  A  bargainl 

Microf  lect  Towers 

Aluminum  towers  may  be  harder  to 
manufacture,  but  they  sure  have  a  lot  of 
advantages  for  the  fellow  who  has  to  put 


them  up  and  use  them. 

First  of  all,  of  course,  they  weigh  but  a 
fraction  of  what  we  are  used  to  with  steel 
towers  .  .  .  about  one  third  as  much,  A  ten 
foot  section  weighs  only  12y2  pounds!  This 
may  not  mean  a  whole  lot  to  you  when  you 
are  dawking  it  around  on  the  ground,  but 
when  you  are  putting  the  sections  one  on 
top  of  the  other  up  in  the  air  you  will  bless 
every  last  pound  that  you  don't  have  to 
struggle  into  place. 

The  weiglit  makes  an  enormous  dif- 
ference if  you  have  your  tower  hinged  at  the 
bottom  for  easy  work  on  the  beam  and 
rotator.  It's  the  difference  between  walking 
a  72  pound,  sixty  foot  tower  into  place  and 
walking  a  212  pound  monster  into  place. 
One  man  vs,  maybe  three  to  do  the  job. 

Some  towers  are  just  terrible  for  climb- 
ing.  Those  diagonal  struts  hurt  the  feet  and 
are  dangerous  if  at  all  damp.  The  Micro  fleet 
tower  is  different.  Some  genius  thought 
ahead  a  little  bit  and  decided  that  it  would 
be  a  good  idea  to  build  flat  step  segments 
into  each  brace.  The  result  is  a  tower  that 
you  can  walk  right  up. 

Aluminum  towers  can't  rust,  of  course, 
and  never  need  any  paint.  They  look  great 
when  you  put  them  up  and  look  just  as  great 
years  later. 

For  a  catalog  and  prices  send  to  Micro- 
fleet,  3575  25th  S.  E,,  Salem,  OR  97302. 

73  Tests  the  Gfobeplotter 

One  of  the  cleverest  ideas  for  beam 
aiming  at  DX  to  come  along  in  recent  times 
is  the  Megert  Globe  Plotter,  Tliis  consists  of 
a  six  inch  world  globe  sitting  up  on  a 
pedestal  with  a  beam-path  indicator. 

To  use  this  gadget  all  you  have  to  do  is 
turn  the  globe  so  that  your  station  location 
is  beneath  the  locating  circle  on  the  top  of 
the  stand.  Then*  as  you  turn  the  pedestal, 
you  can  read  the  beam  heading  of  any  city 
that  falls  under  the  beam-path  indicator. 
Charts  and  regular  world  globes  are  all  well 


112 


73   MAGAZINE 


^ 


and  good,  but  there  is  absolutely  nothing 
like  having  a  globe  mounted  with  your  home 
on  its  axis.  For  the  first  time  you  will  be 
able  to  see  how  the  great  circle  paths  really 
swing.,, and  how  your  signals  travel.  If  youVe 
ever  wondered  why  your  beam  heading  is 
almost  the  same  for  Brazil  as  it  is  for  South 
Africa,  the  question  will  be  dispelled  when 
you  swing  your  Globe  Plotter  around. 

Andj  since  the  globe  is  not  permanently 
fixed  in  place  (unless  you  glue  it  to  the  three 
pillars  that  hold  it  to  the  pedestal)  you  can 
easily  swing  it  around  to  any  other  location 
and  get  the  beam  heading  from  there  to  any 
other  spot  in  the  world.  If  a  station  in 
Germany  is  working  New  Zealand,  do  you 
think  he  could  here  you?  The  plotter  will 
tell  you  immediately. 

You  don't  have  to  scrunch  over  to  see 
what  the  other  side  of  the  world  is  iike.„GP 
has  a  built-in  mirror  for  looking  at  Australia 
and  environs. 

The  Globe  Plotter  is  just  under  10"  high 
and  is  mounted  on  a  nice  looking  base.  Price 
is  $17.95  by  mail  order  from  Megart^  Box 
2097,  Des  Moines,  Iowa  50310, 


Does  Math  scare  you? 
"Simplified  Matli  for  itie  Ham  Sliack" 

One  of  Us  books  will  make  it  easy. 
Order  today,  only  50c. 


PROPAGATION  CHART 

J,  H,  Nelson 

October  1969 


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A-Next  higher  frequency  may  be  useful  this  period 
B— Difficult  current  this  period 


OCTOBER    1969 


113 


used     to     coat 


Across 

1 .  Also  called  a  ham* 

4.  Electronic  path  be- 
tween 2  or  more  paths 
providing  a  number  of 
channels, 

7,  Type  of  tree. 

8-  Logarithniic      expres- 
sion     of     ratios     of 
power. 
10.  Ampere,  Abbr. 

12.  Electromagnetic  unit. 
Abbr, 

13.  A  generator  that  pro- 
vides field  current  for 
an  AC  generator. 

14.  Organ  of  sight, 

15.  Megohm.  Abbr. 
17.    Basic  unit  of  work  in 

the  cgs  system. 

19.  Period  immediately 
before  some  event. 

20.  Surrounding. 
23.  Used  in  T.V,  receivers 

to  supply  high  DC 
voltage  required  by 
the  second  anode  of 
cathode-ray  tubes, 

26.  Chemical     compound 

recording  discs. 
28.  Audio  amplifier  frequency  equal  to  the 

square    root    of    the    product    of   two 

half-power  frequencies. 

30.  Maiden  name. 

31.  International  Radio  Association,  Abbr, 
33,  G.l.  club. 

35.  Affirmative  side. 

36.  A  type  of  battery, 

37.  To  move  with  pressure  and  friction. 

38.  Short  sleep. 

40,  Surface  between  two  adjacent  grooves 

on  a  recording  disc. 
42-  Period  of  time. 

43,  A   device  that  introduces  inductive 
capacitive  reactance  into  a  circuit. 

44.  Process     of    entering    information 
answers  via  the  agency  of  a  printer. 

Down 

1.  A  means  for  radiating  or  receiving  radio 
waves* 

2.  Short  wires  used  to  connect  open-line 
wires  to  insulators. 

3.  Stepping    relay  actuated   by   an   arma- 
ture-driven 

4.  Prolonged     undesirable     opening     and 
closing  of  elecrtical  contacts. 

5*  Used  in  mechanical  push-button  tuning 
systems. 


or 


or 


6.  Speaker  designed  for  treble  frequencies. 

8.  Worthless  person. 

9.  A  section  or  branch  of  a  component  or 
system, 

10.  Unit  of  surface  measure  in  the  metric 
system. 

11.  A  sliort  pin  or  bolt. 

16.  End  section  of  a  transistor. 
18.  Also  called  diamond  antenna, 

21,  Male  nickname, 

22,  Partner  of  bolt. 

24.  Weekday,  Abbr, 

25.  Indefinite  period  of  time. 

26.  A  fitting  designed  to  change  the  termi- 
nal arrangement  of  a  jack,  plug  or 
socket. 

27.  Sometimes  called  matrix, 

28.  Absolute  unit  of  pressure. 

29.  A  type  of  dipole  antenna. 

31,  Atom   which   has  fewer  or  more  elec- 
trons than  normal, 
iJt^  oinaKe. 

33.  Stations  capable  of  direct  communica- 
tions on  a  common  channel. 

34.  A  globe  or  sphere. 

39,  Discharge  of  electricity  through  a  gas, 

41,  Also.  ^,,  ^     ,  ^ 

.  .  ,  Michael  Kresila 

SoluVion  on  p^qB  122 


114 


73  MAGAZINE 


The  ESSCO  Mode*  TU-7  Teleprmter 
Deinodulator  is  a  completely  assem- 
bled, ready  to  run  system,  fufly  wired 
with  loop  supply,  connectors,  tuning 
indicator,  reversing  switchi  modufar 
tracks,  scope  outputs,  50  ua  2ero 
center  meter,  function  switch  and 
famous  ESSCO  solid  state  modular 
plug-in  units. 


*0»ii 


■♦■^^^ 


ESSCO's  Complete 

SoUd  St<sUe 


RTTY  DEMODULATOR 


TU-7B  DUAL  CHANNEL  KfT 

TU-7     (As  above)  Factory  wired,  tested  &  guaranteed 

TU-7C  SINGLE  CHANNEL  KIT 

TU'7D  (As  atx}ve)  Factory  wired,  tested  &  guaranteed 


$138.25 
$163.00 
$132.25 
$156.25 


Model  TU-7C 


'*  uelet^e  SpecialiAts' 

324    ARCH  STREET     CAMDEN.   N.  J 


Phan«:  (609)  36S-6in 


a  dollar  a  copy?  RIDICULOUS  I 


It  may   be  rrdfculous,  but  it  is  also  not  far  in 

the  future.  The  dollar  won't  make  us  rich,  either. 
We  hope  that  it  will  bring  us  back  into  the  black, 
and  thaf^s  about  it. 

What  happened  to  bring  on  this  substantia! 
increase?  Two  things.  First  and  foremost  was  the 
July  increase  in  postal  rates.  This  was  the  biggest 
rate  increase  yet  for  us  ,  .  .  and  we  are  paying 
over  50%  more  in  postage  now  than  we  were  a 
year  ago*  The  5%  profit  we  made  last  year  just 
broke  us  even  with  inflation,  so  we  found 
ourselves  working  like  the  devil  to  break  even. 
Now,  with  the  new  postal  rates,  we  will  work 
ourselves  sitly  for  a  handsome  net  loss.  Something^ 
has  to  qi\f&  *  .  »  and  that  means  you,  the  reader. 


#  •  • 


NAME 


it  fs  not  all  g?ve  and  no  take,  by  any  means, 
however.  Just  look  at  the  size  of  this  issue  of  73. 
We've  been  running  144  pages  a  month  or  better 
since  May  and  intend  to  keep  it  up.  When  you 
figure  that  we  are,  month  after  month,  bringing 
you  more  feature  articles  than  all  three  other 
magazines  combined,  then  the  quarter  extra  isn't 
all  that  bad  a  deal. 

Of  course  there  is  still  time  to  hedge  against 
the  increase  by  buying  a  subscription  right  now, 
before  the  subscription  rates  go  up,  too.  We'll 
accept  a  three  year  extension  of  your  present 
subscription  at  the  current  rates  .  .  ,  but  don't 
expect  to  be  able  to  take  advantage  of  this  for 
much  longer.  By  next  month  we  may  have  to  roll 
out  the  new  subscription  rates  for  you. 

CALL 


ADDRESS 

STATE 


CITY 


D  I  WANT  THE  $12  BARGAIN  RATE  FOR  THREE  YEARS 

D  IXL  TAKE  ONE  YEAR  AT  THE  $6  RATE 

D  THIS  IS  A  RENEWAL 

D  ENCLOSED  IS  CHECK.  CASH  OR  MONEY  ORDER 

73   MAGAZINE    PETERBOROUGH,   NEW   HAMPSHIRE   03458 


OCTOBER    1969 


115 


man 


A.  David  Mtddelton  W5CA/V/7ZC 

Box  303 

Springdale,  UT  84767 


or    The     Tale    of     Two     Kitties 


I  should  have  realized  what  was  going  on 
when  those  QSL  cards  would  not  check  out 
with  my  log!  My  memory  did  not  include 
any  recollection  of  QSOs  with  those 
stations,  and  there  were  no  entries  for  them 
in  my  log  book. 

Before  getting  any  deeper  into  my 
problem,  let  me  explain  the  W5CA  station 
set-up.  My  garage-han>shack  is  a  Santa  Fe 
railroad  boxcar,  of  the  old  wooden  type.  It 
is  44  feet  long  and  makes  an  excellent  garage 
for  my  Buick.  By  adding  a  partition  1  made  a 
cozy  hamshack  and  workshop  in  the  end  of 
the  old  box  car.  The  shack  has  comfortable 
old  chairs,  a  battered  sofa  and^  of  course,  the 
rig  and  workbench,  plus  tlie  usual  pile  of 
surplus  gear. 

The  YF  and  I  are  cat  lovers  and  have 
always  shared  our  home  and  household  with 
cats.  Currently  we  have  two  furry  friends; 
Golden  Nugget  3rd,  and  Ebony,  a  jet  black 
cat  two  years  younger  than  old  Nugget  who 
is  twelve.  Both  are  fine  cats  and  friends. 

Long  ago,  I  thought  up  a  convenient 
method  of  letting  our  cats  in  and  out  of 
their  quarters.  I  cut  an  opening  in  an  outside 
wall,  overlaid  with  pieces  of  canvas  to  keep 
out  the  wind-  unwanted  dogs,  and  yet 
permit  the  cats  to  go  in  and  out  of  their 
home  without  bothering  us.  Such  a  "cat 
door'*  was  placed  in  the  tjox  car  wall  so  that 
the  cats  would  have  a  snug,  warm  place  to 
sleep  or  to  hide  out.  The  only  human  access 
to  the  shack  is  a  door  that  is  kept  locked  to 
protect  the  rig  from  "unauthorized  usage". 
Or,  so  1  thouglu! 

1  practice  the  old  habit  of  leaving  all 
filaments  burning  on  the  rig  and  the  receiver 
fully  fired  up.  All  it  takes  to  get  on  the  air  is 
to  punch  a  push-button  switch  on  the  table. 


This  energizes  the  input  to  the  transmitter 
power  supplies.  A  foot  switch,  when  pressed, 
completes  the  relay  circuits  and  the  rig  is  on 
the  air,  subject  to  keying.  With  the  fool 
switch  up,  the  receiver  is  back  in  action.  As  1 
said  before,  1  should  have  known  better! 

Looking  back,  I  recall  that  Nugget  spent 
an  awful  lot  of  time  in  the  shack.  1  presumed 
that  both  cats  slept  there  at  night  but,  even 
in  the  daytime,  there  was  usually  a  cat 
snoozing  away  on  the  sofa  or  in  one  of  the 
old  chairs. 

Nugget  was  also  a  frequent  guest  on  the 
operating  table.  Tliis  began  when  he  was  still 
a  small  kitten.  He  was  fascinated  by  the 
IIRO  dial  and  entranced  when  the  colored 
pilot  light  jewels  lit  up.  The  Panoramic 
adapter  'scope  pattern  seemed  to  attract  his 
attention  and  the  wiggles  of  the  'scope 
pattern  almost  hypnotized  the  cat.  He  would 
sit  by  the  hour  and  watch.  As  he  grew  older^ 
liis  long  whiskers  would  twitch  as  the  CW 
screeched  out  of  the  cans  perched  high  on 
my  head.  Ebony  was  not  so  impressed  and 
gave  the  rig  and  its  operation  scant 
attention. 

Another  thing  I  should  have  noticed  was 
Nugget's  staring  at  the  QSLs  pinned  on  the 
wall  and  ceiling.  He'd  sit  by  the  hour,  golden 
head  cocked  to  one  side,  peering  at  the  cards 
with  their  bright  numerals  and  hitricate 
patterns. 

Then  one  day  1  added  a  new  one- 
FEIINE.  Shortly  after  this,  things  began  to 
happen  that  were  beyond  my  comprehen- 
sion. I  have  always,  like  most  active 
amateurs,  received  a  few  QSLs  that  would 
not  check  out.  Even  inactive  hams  some- 
times receive  them!  Fd  had  my  share  of 
unknowns,  but  now  there  were  more  than 


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73  MAGAZINE 


normaL  1  pile  up  my  incoming  cardSj  and 
some  evening  when  the  band  is  dead  I  sort 
them  out,  check  them  against  the  log,  record 
their  receipt  and  then  fiU  out  answers. 

This  one  evening  there  were  several  cards 
which  would  not  fit  into  my  records.  There 
were  the  usual  W  and  K  cards,  many  of 
which  were  from  guys  so  anxious  to  work 
New  Mexico  that  they  overlooked  making 
the^  necessary  QSO  first.  But  there  were 
several  DX  cards  in  the  pile  and  they  did  not 
show  up  in  the  log.  This  should  have  been 
warning  enough,  but  as  I  said,  I  was  not 
hep"  not  yet! 

I  filed  away  those  inexplicable  cards  with 
my  collection  of  swl  cards,  sighing  as  I  did, 
for  there  were  some  really  rare  ones  in  this 
new  group  of  "unknowns**. 

A  few  days  latex  our  5th  call  area  QSL 
Bureau  sent  me  another  batch,  and  with 
those  cards  was  a  scribbled  note  from  Brad, 
W5ADZ,  our  QSL  sender-outer  and  noted 
DXer.  His  note  read-"OM,  you  sure  have 
some  goodies  in  this  batch.  This  makes  me 
drool  to  see  such  choice  morsels  go  out  to 
you.  What  special  calling  formula  do  you  use 
at  Tijeras,  or  is  it  merely  the  altitude? 
Lemme  in  on  the  secret/* 

I  spread  out  this  new  batch  of  cards 
which  had  evicted  a  comment  from  blase 
Brad  J  who,  I  thought  must  have  seen 
everything  in  the  line  of  DX  himself.  No 
wonder  Brad  had  mentioned  these  cards. 
Here  is  the  list,  just  as  I  wrote  them  down  on 
the  back  of  a  log  sheet,  ME^UW-URIKAT- 
CAITS"  PU3SS-  MJJUSE-  YLIKIT- 
UPIPUS!  I  was  sitting  there  mulling  over 
these  rare  cards  when  I  chanced  to  look  over 
at  the  old  sofa.  Ebony  was  asleep  but  Nugget 
was  obviously  "playing  possum".  I  could  see 
his  eyes  gleam  through  narrowed  lids.  He 
was  far  from  asleep.!  I  had  been  picking  up 
the  cards,  one  by  one,  examining  them,  and 
then  I  placed  them  face  up  on  the  table. 
Nugget  looked  as  if  he  was  watching  me,  so  I 
tested  him  by  holding  up  the  colorful 
YLIKIT  QSL.  Nugget's  long  white  whiskers 
twitched  and  I  could  see  him  drool,  as  cats 
do  when  they  are  pleased  or  excited  about 
something.  The  look  in  the  cat's  eyes  was 
enough  to  tip  me  off,  but  how  dumb  can  we 
humans  be?  There  was  still  another  clue  to 
the  mystery  but  I  muffed  it,  also.  At  W5CA 


I  use  an  elapsed -time  meter  across  the  ac 
input  to  the  transmitter  plate  supplies.  This 
meter  records  the  actual  time -on-air  of  the 
transmitter.  I  took  a  look  at  the  readings  for 
the  past  few  months.  My  figures  showed  that 
there  was  more  time  on  the  meter  than  a 
quick  inspection  tallied  on  the  log.  But,  1 
merely  made  a  mental  note  to  keep  better 
records  and  put  down  the  discrepancy  as 
lousy  bookkeeping. 

I  continued  to  wonder  about  those 
"goodies"  as  Brad  called  them  and  regretted 
the  fact  that  they  could  not  be  counted  in 
any  awards  or  totaL  I  did  not  even  recall 
hearing  such  stuff  as  ME0UW,  although 
there  had  been  some  really  screwy  calls 
issued  in  the  past  few  years.  Yet-  there  was 
something  that  bugged  me  about  those 
QSLsf 

A  few  evenings  later  I  got  out  those 
strange  cards  and  spread  them  on  the  table. 
Nugget  was  sitting  on  the  end  of  the 
operating  table  looking  out  the  window,  I 
noticed  that  he  kept  slyly  turning  his  head 
to  watch  me  lay  down  the  QSLs.  When  I  put 
down  the  pretty  one  from  YLIKIT  I  saw  a 
furry  paw  reach  out  and  give  the  card  a  pat  I 
The  paw  drew  back  lightning-quick  as  the 
cat  obviously  did  not  wish  me  to  see  his 
actions.  He  sat  there-  silently  and  with  not  a 
whisker  twitching.  Then  he  resumed  looking 
out  the  window. 

Suddenly,  as  it  so  often  does,  the  band 
came  alive  and  KAITS  came  blasting  in,  the 
cans  screeching  out  his  call.  The  KA  signed 
and  I  looked  at  Nugget.  His  eyes  were  open 
in  a  wicked  fashion.  His  right  front  paw 
stiffened  and  reached  out  toward  the  key. 
The  cat  started  to  tap  on  the  Navy  knob! 
Shocked  speechless  and  motionless,  I  just  sat 
there.  Nugget  saw  me  stare  at  him  and  drew 
back  his  paw  and  began  a  careful  inspection 
of  the  sheathed  claws,  completely  indif- 
ferent to  my  bewildered  glance  as  he  took 
refuge  in  a  routine  cat-type  operation-  paw 
inspection. 

1  have  been  a  ham  for  over  forty  years, 
boy  and  man,  but  what  followed  is  the 
weirdest  thing  1  ever  had  happen  to  me! 

Startled,  I  said  out  loud,  "I'U  be-'\  A 
furry  paw  shot  out  and  I  heard  the  key  click 
out  "BK  BK*'  as  the  cat  manipulated  the 
key. 


OCTOBER    1969 


117 


1 

•4 


Incredible  thoughts  raced  through  my 
brain-  Could  my  pet  understand  what  I  say? 
To  test  liim,  1  spoke  out  firmly,  "Look  here, 
Nugget!  Can  you  understand  my  speech? 
Can  you  send  Morse  code?" 

He  did  not  hesitate.  The  cat's  paw  acted 
and  the  key  clicked  "C'\  1  gasped  and 
muttered,  half  to  myself,  "Oh,  a  traffic 
man!" 

"Not  me,  OM"  came  the  clicked  reply,  "I 
just  know  all  the  tricks."  The  cat  looked 
smugly  at  me  as  I  sat  there  bewildered  and 
amazed. 

As  I  sat  there  looking  at  my  unbelievable 
pet  he  jumped  from  the  table  to  the  work 
bench  where  there  was  a  transistor  code 
practice  set.  He  stood  over  it  staring,  until  I 
reached  for  it  and  picked  up  the  set  and  put 
it  on  the  operating  table.  Nugget  immediate- 
ly moved  close  to  the  practice  key  and  sat 
there-  waiting, 

I  saif  out  loud,  **Let's  get  this  matter 
straightened  out."  I  paused  and  continued. 
**So  you  understand  when  I  speak  to  you?" 
Then  came  the  answer  that  almost  rocked 
me  from  my  chair.  "Sure,  OM,  Ail  us  cats 
dig  English,"  The  tiny  loud  speaker  on  the 
code  practice  set  rang  out  this  unexpected 
reply  as  the  cat  skillfully  manipulated  the 
key, 

"How  long  have  you  understood  human 
talk?" J I  quickly  queried  the  cat, 

"That  is  the  second  most  important  thing 
we  learn.  First  comes  eating,  and  then  comes 
language."  The  cat  seemed  very  sure  of 
himself  as  he  pounded  out  the  code  in  a 
precise  fashion. 

"Why  don't  you  ever  speak  to  us?"  I 
inquired, 

"We  do,  but  you  dumb  clods  can't  hear 
us  cats  talking!"  The  golden-furred  face  bore 
a  smirking  look.  I  could  see  I  was  being 
forced  into  a  corner,  so  1  tried  another  angle 
of  attack, 

'Took  here,  Old  Cat,  What  about  your 
operating  on  code?  Isn't  that  unusualV^ 

'Well,  OM.  I  am  getting  through  to  you 
on  CW,  Right?" 

**How   about   the   rest  of  you  cats?",  I 
asked  my  pet- 
Nugget    drew    himself   up    proudly    and 
replied    in    well-sent    Morse:    "That    is    a 
different   story.   Very  few  cats  can  pound 


brass.  Most  cats  are  'tone  men'.  If  you  don't 
believe  it,  just  listen  in  on  any  phone  band 
and  hear  all  the  cat-calling  and  squeals, 
especially  on  AM  fone." 

I  muttered  to  myself,  ''He*s  got  some- 
thing  there!"  But,  being  undaunted,  I 
plunged  in  even  deeper  as  I  queried,  "How 
did  you  learn  the  code?" 

^'It  was  this  way.  You  always  leave  the 
receiver  going  full  blast.  Right?  And,  you 
know  how  some  signals  just  seem  to  drift 
back  and  forth  across  the  dial?"  1  knew  just 
what  he  meant. 

The  cat  went  on,  **That  is  the  way  I 
started.  I  lay  here  trying  to  get  some  rest 
after  a  hard  night  out^  but  that  CW  kept 
whistling  in  my  ears,  Vd  hear  a  station  call. 
Then  another  would  answer  him.  I  got  so  I 
could  read  letters.  Then  came  whole  calls 
that  I  could  catch.  Finally,  1  got  so  I  could 
copy  whole  QSOs."  The  cat  stopped  and 
looked  at  me,  but  I  said  nothing  so  he  went 
back  to  his  brass  pounding- 

"Soon  as  I  got  *over  the  hump'  it  was 
easy,  OM.  Later  I  found  out  about  tuning 
and  happened  to  tune  in  a  code  practice 
session.  Then,  I  listened  whenever  1  could 
hear  Wl  AW  and  W60WP.  That  is  when  some 
lid  did  not  smother  their  code  practice 
transmissions  with  QRM.  Say?  OM!  Do  you 
think  I  could  get  a  Code  Proficiency 
Certificate  from  ARRL?"  The  golden-haired 
puss  looked  up  at  me,  with  great  pride  in  his 
huge  yellow  eyes, 

"Come  now!  You  don't  think  I  believe 
that  you  have  qualified  for  a  CPC."  I  did  not 
give  him  a  chance  to  reply  but  pushed  right 
on  into  my  next  question.  "How  did  you 
learn  to  send?" 

Back  came  a  snappy  answer  in  the  form 
of  another  question.  My  cat  was  up  to 
people-type  tricks!  "How  did  you  learn?", 
he  sent. 

Without  thinking,  I  replied,  **Why,  all  us 
Young  Squirts  learned  by  tapping  out  code 
on  a  desk  or  table  with  our  fingers."  I 
looked  at  Nugget  who  did  not  seem 
impressed,  so  I  added,  "We  even  had  QSOs 
that  way." 

"Why  not?",  snapped  the  cat,  "IVe  tried 
lots  of  times  to  raise  you,  but  OM,  you  sure 
are  slow  on  the  up  beat!"  Then  the  cat  really 
set  me  back  on  my  heels  as  he  told  me  his 


118 


73  MAGAZINE 


theory  of  learning  the  code,  "Once  my 
subconscious  mind  had  mastered  the  code  it 
was  easy  for  it  to  transfer  this  ability  to 
digital  functions  and  what  happened?  I 
could  pound  brass  as  well  as  receive."  The 
cat's  face  was  full  of  smugness  as  he  sat  back 
and  waited  for  my  reply, 

"Was  it  you,  Old  Cat,  who  ran  down  the 
batteries  in  the  code  practice  set?"  I  asked  in 
an  accusing  tone. 

"Sure,  I  had  trouble  operating  that  little 
switch  so  I  just  left  it  on  all  the  time/' 

"So-  you  learned  to  copy  and  to  send 
CW,  Now  tell  me,  how  did  you  work  the  rig 
and  the  receiver?  What  about  the  foot 
switch,  Old  Cat,  how  did  you  use  that?" 

I  looked  so  scornfully  at  my  cat  that  he 
lowered  his  head  but  tapped  out,  "Ebony 
was    my   second    operator  and    foot-switch 


mam 


ff 


1  looked  around  for  the  black  pussy  cat. 
Ebony,  but  he  was  not  in  the  shack.  The 
golden-furred  paw  went  on  and  continued  to 
send  flawless  code  to  tell  me  this  amazing 
story,  "I  tried  to  get  Ebony  to  learn  the 
code  so  he  could  operate  as  weU  as  I,  But  he 
would  not  practice  and  he  thought  it  was 
not  worth  the  effort.  Oh,  he  learned  to  read 
and  to  send  calls,  and  he  could  even  hold  a 
simple  QSO.  But,  let's  face  it*  He  was  never  a 
hep  cat  on  CW-" 

"Tell  me.  Nugget,  How  did  you  work  the 
rig?  The  foot  switch?  That  takes  coordina- 
tion!" 

"OM,  I  sit  in  front  of  the  receiver,  like 
this."  The  big  cat  moved  over  in  front  of  the 
HRO  and  put  one  paw  on  the  huge  diaL  This 
dial  turned  easily  due  to  its  well-wom 
smoothness  through  years  of  use.  The  cat 
moved  the  dial  with  practiced  ease.  He  then 
returned  to  the  practice  set  and  sent,  "That's 
the  way  I  tune  the  receiver.  Then  1  hit  the 
key  at  just  the  riglit  instant." 

"The  foot  switch?  What  about  that?"  I 
implored.  "How  did  Ebony  know  when  to 
press  the  switch?" 

**We  cats  have  our  own  private  means  of 
communication  and  it  sure  beats  electronics. 
Not  a  tube  or  even  a  transistor,"  The  cat 
seemed  to  sneer  as  he  manipulated  the  key 
with  precisely-formed  characters, 

I  had  no  reply  as  that  comment  only 
substantiated  what  I  had  long  believed  about 


OCTOBER  J969 


animal  communication. 

The  cat  went  on  sending.  "I  tell  Ebony 
when  to  press  the  foot  switch  and  he  knows 
from  my  sign  off  when  to  release  it*" 

I  had  about  reached  the  limit  of  my 
credulity  and  was  about  to  blow  my  stack 
but  1  took  one  more  chance  and  ordered- 
"OK!  Old  Cat,  let  me  see  an  actual 
demonstration/* 

Nugget  shrugged  a  whisker  and  reph'ed  on 
the  key,  "Why  waste  the  juice?  You  know 
the  band  is  dead/* 

I  was  in  no  mood'  to  argue  with  a  cat. 
**Never  mind  that.  I  want  to  see  you  operate. 
Dead  band  or  live  band.  Hop  to  it!  '* 

'OK,  OM.  If  you  insist-  QRX  one." 
Nugget  jumped  from  the  table  and  darted 
out  the  cat*s  door  to  the  outside.  In  a  few 
minutes  he  was  back  close-herding  a 
reluctant,  paw-dragging  Ebony,  The  black 
cat  crouched  on  the  floor  beneath  the 
operating  bench,  obviously  st0  half  asleep. 
Ebony  looked  up  at  me  with  a  mournful, 
resigned  look.  This  being  drafted  to  help 
operate  was  nothing  new  to  him  and  not 
very  pleasant  either,  his  sad  eyes  impMed, 

Nugget  said  something  in  cat  talk  to  his 
assistant  operator  which,  naturally,  I  could 
not  hear.  Ebony  moved  over  and  crouched 
near  the  foot  switch.  There  he  sat, 
Sphinx-fashion,  paw  on  board,  waiting  a 
command. 

Let's  see  you  cats  raise  someone.  Any 
one!"  1  demanded. 

Nugget  smirked  at  me,  whiskers  twitch- 
ing, but  moved  to  the  HRO  and  sat  up  on  his 
hind  quarters.  With  infinite  patience  and 
considerable  finesse,  he  slowly  rolled  the  dial 
by  applying  paw  pressure  to  one  side.  1 
heard  a  loud  signal  calling  CQ<  The  paw 
stopped  and  the  CQ  ended.  It  was  K9DOG. 
The  signal  was  loud  and  clear.  The  cat 
ignored  it  and  continued  tuning  over  the 
band.  Puzzled,  I  inquired,  "Why  not  him?'* 

Nugget  jumped  to  the  practice  set  and 
repUed,  "OM,  we  cats  do  have  our  pride." 
Then  he  strutted  back  to  the  HRO.  Tuning 
around  he  brought  in  another  CQ  and  the 
letters  of  the  call  were  C  A  T.  The 
cat-operator  slipped  a  paw  and  nudged  the  rf 
gain  control.  The  signal  rose  to  a  more 
readable  level  and  the  cans  rattled  out  the 
code.  Nugget  raised  up,  pressed  the  spotting 


119 


C£' 


1 


1 


Micro-Switch  on  the  vfo  and,  with  his  other 
front  paw^  carefully  tuned  the  variable 
oscillator  to  zero  beat.  Then  he  relaxed,  paw 
on  key  until  the  stated  signed-  It  was 
K8CAT. 

My  two  pets^  by  their  own  communica- 
tion method  undetectable  by  humans,  were 
in  contact  and  ready  to  go  into  action.  The 
black  puss  was  almost  asleep,  and  relaxed, 
but  at  just  the  proper  instant  down  went  the 
black  paw,  the  foot  switch  closed,  relays 
clattered  and  W5CA  was  on  the  air!  I 
watched  speechless  with  amazement! 

Nugget  tapped  out  a  sharp  3  x  3  call  and 
sent  AR,  His  co-operator  under  the  table 
raised  his  paw,  the  relays  snapped  over  into 
"receive**  position  and  I  heard  K8CAT  come 
back  with  a  good  report  to  which  he  added, 
"You  must  be  a  visitor  at  W5CA.  That  fist 
does  not  have  Mid's  Lake  Erie  swing." 

1  could  stand  this  incredible  sequence  of 
events  no  longer  so  I  reached  for  the  key, 
iust  beating  Nugget  to  the  Navy  knob  by  a 
whisker*s  width.  I  sent/*rfti!T  is  Mid*  The 
other  operator  was  my  cat."  I  stood  by, 
TliciL  was  a  long  pause— 

"Did  you  say  your  c,a,t?"  inquired  the 
distant  8, 

*'Yes,  OM."  1  repeated,  "my  cat."  1 
looked  over  at  Nugget  who  was  now  engaged 
in  a  microscropic  examination  of  his  left 
paw.  He  showed  only  indifference  on  his 
golden  face.  I  looked  down  at  the  black  cat, 
Ebony.  He  was  still  crouched  at  the 
foot-switch  with  a  paw  in  the  "ready" 
position. 

K8CAT  was  still  unconvinced  as  he  asked ^ 
**You  mean  a  feline  animal?  A  pussy  cat?" 

This  time  Nugget's  paw  beat  my  hand  to 
the  key  and  he  replied^  "Sure— a  cat.  I  am 
twelve  years  old,  name  is  Nugget.  I  have  a 
golden  coat  and  a  long  fluffy  tail  BK." 

There  was  a  vast  quiet  on  the  frequency. 
Then  came  a  stuttering  sound  of  characters 
incoherently  formed.  Finally  the  dots  and 
dashes  dribbled  off  into  gibberish.  Then— 
more  silence  and  lots  of  it! 

Nugget  looked  at  me  and  I  am  sure  he 
shrugged  his  whiskers.  His  look  said-well, 
that  guy  just  could  not  take  it.  The  cat 
seemed  unmoved  by  the  distant  amateur's 
confusion, 

I  reached  for  the  log  book  to  record  the 


ill-fated  QSO  with  K8CAT.  Tliat  action 
brought  back  a  flood  of  memories  and  raised 
some  pointed  questions  in  my  mind.  What 
about  those  uncheckable  QSLs?  Such  an 
event  could  have  brought  in  QSLs  from 
those  "unknowns". 

Then  the  shack  roof  fell  in  on  me! 
ME0UW-M?)USE  and  YLIKIT!  Could  it  be 
that  my  cat  operators  were  that  selective? 

The  golden  cat  moved  over  to  the 
practice  key  and  resumed  our  cross-band 
QSO  in  his  excellently-sent  code.  "Only  the 
good  DX.  Ebony  worked  some  of  the  locals. 
He  does  not  dig  DX  like  I  do.  Besides,  he  has 
a  lousy  fist-1  mean  paw.  I  don't  let  him 
operate  often," 

I  glanced  at  Ebony  but  he  appeared  to  be 
sound  asleep.  Perhaps  he  was  and  had  not 
heard  Nugget's  slanderous  remark,  or  per- 
haps the  code  was  just  a  bit  too  fast  for  him, 

"Perhaps,  OC,"  I  continued,  "y*^^  wquld 
care  to  tell  me  how  you  learned  about  bX 
and  what  is  choice  DX?"  My  voice  was  mofe 
respectful  as  the  awsome  facts  began  to  sink 
in. 

'i  read  QST's  *HOW'S  DX\  You  always 
leave  the  magazine  open  at  that  page,  OM" 
sent  my  intelligent  pet, 

"Now,  Nugget!"  I  said  with  triumph  in 
my  voice,  "I've  got  you!  It  takes  a 
magnifying  glass  to  read  that  fine  print  in 
QST," 

"BK-"  sent  the  cat,  '"^you  know  that  us 
cats  are  very  proud  of  our  keen  eyesight, 
Why^  OM,  I  can  even  read  the  addresses 
listed  in  the  call  bookV^  Nugget  was  really 
smirking  now. 

That  did  it!  I  realized  that  this  discussion^ 
while  enlightening,  was  not  placing  human 
beings  in  a  favorable  light.  I  leaned  down 
and  picked  up  the  sleep -limp  Ebony.  I 
placed  him  by  the  practice  key  and  said, 
"Let's  hear  your  fist^  Ebony!*' 

Nugget  must  have  said  something  to 
Ebony.  The  little  black  cat  put  out  a  stiff 
paw  and  slowly  tapped  out  in  uneven 
characters-"Ur  s  igshere  5  59Q  T  HTijer  as 
Ne  w  Mexic  o  handlehereEbony  how  cpyb  k 
toyou,"  Ebony  relaxed  in  a  heap  beside  the 
key. 

Nugget  shot  out  a  paw  and  sent  briskly, 
"You  see  what  1  mean,  OM  He  has  listened 
to    and   worked    too   many    Novices."   The 


120 


73  MAGAZINE 


RCA  TV-EYE.  See  QST  Nov.  1962  for 

Amateur  Television  Transmitter  use. 

May  be  wfred  for  Video  or  RF  output.  Camera  head  with  controf,  test  vidicon  and  schematic,  less 

lens.  #6 130-Used-$  139.95. 

Ask  for  new  free  flyer  969S1  -listing  this  and  other  incredible  bargains. 

DENSOIM  ELECTRONIC  CORP. 

(203)875-5198  Rockville.  Conn.  06066  I 


PO  Box  85,  Longview  St; 


golden-furred  cat  seemed  almost  ashamed  of 
his  companion's  inept  operating  skill.  '*But", 
the  sending  continued,  **he  is  really  a  sharp 
foot-switch  man/* 

i  was  chagrined  at  aU  these  proceedings 
but  yet  I  was  determined  to  add  some 
reproachment  for  the  cats 'actions.  "Look 
here,  you  furry  scoundrels.  What  about  FCC 
regulations  regarding  'unauthorized  opera- 
tions'? What  about  Rule  12.1?" 

Nugget  broke  me  on  the  practice  key  and 
replied.  **You  mean  where  it  defines  an 
*amateur'  as  a  person  interested  in  radio 
technique?  The  FCC  cannot  bother  us  cats. 
Cats  are  not  persons!" 

I  could  think  of  no  fitting  response  to 
that  obvious  truth  so  I  pressed  on  to  another 
point.  "How  come  you  never  filled  in  the  log 
or  answere  any  of  those  QSLs?"  My 
questions  were  almost  a  sneer. 

Nugget's  reply  was  the  coup  de  grace  as 

he  snapped  back.  "Who  ever  heard  of  a  cat 

who  could  writeV 

.  .  .  W7ZC 


What's  with  UFO's  ? 


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on  14,300  kc 


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500  Ledyard   St.,  Harrford,   Conn.  06114 

203-527-1881 

(1  Block  East  of  Wetherffield  A¥«.  off 

Airport  Rd*,  Rte  6) 

T«rephone:    20^-527-1881 

Soo  CORKY,   W1KXM  or  WARD,   WJWRQ 

ANTENNA  STUFF 


In  100  foot  rolls  only 

450  ohm  open  wire.  Per  100  feet  ,., 
300  ohm  open  wire.  Per  100  feet  *** 
Standoff-Mast  or  Screw-in 


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Ifi   100  ft.  interconnected  coils 

16  CopperweM.  Per   100  feet   ..*$  1.19 

14  Copperweid.  Per  100  feet 
12  Coppefwefd.   Per   ?00  feet   ,,, 
14  Copper-Solid.  Per  100  feet  ... 
12  Copper-Soltd,  Per  100  feet  .., 
Times  T4-50  L/Loss  8U.  Per  foot 
Times  T5^50  L/Loss  SSU,  Per  foot 
Times  Sofid  Sheath  Alumafoam  in 
Kits  with  connectors  50/100  ft 
Glass  Line-guy  wire.  Per  100  feel 
Glass  Lifie^guy  wire.  Per  100  feet 

Hy^Gain    Balun.    Each    ...**•.,,, 14,95 

w^Av  MaiLrn*  cacn  ••#•<  «•<  •  >*«  m*mm»**»*»it*'  ■  i-dtiV^ 
oiitx  ouQ5«  cacn  >•••»•«•«  •«*••«*  ••••■«•«*••«     iuvs 

All  major  lines  of  Amateur  gear  •  Rohn  #25  towers 
and  accessories  •  Waters  Pretax  switches  •  Dow  Key 
relays  •  DP2  Vacationer  (406)  Antenna  27.95  New- 
Ironies   Hustler  Mobile  AU   antenna   insulators  in  stock 

(Canodtan    Amateurs    Send    U.5,    Funds    Only) 

F.D<b.   Hartford 

Flease  Include  Postage 

CONSECTICUT'S  OLDEST  HAM  STORE 


Stock 

500  tbs  Test 
1000  lbs  Test 


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BLUFFTON     OHIO  45817 


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Can  be  read  from  15  feet  in  a  dense  fog. 
Available  in  Charcoal  Grey,  Coral  Red,  Li^ht 
Blue,  White  or  Brown.  If  you  don't  specify 
we  will  send  one  at  random.  They  are  ail 
beautiful.    12  hour  movement  also  available. 

REOLINE  Co.,  Box231,Jaffrey,  NH-03452 


OCTOBER    1969 


121 


I 


Save  That  Manual 

Every  ham  who  has  been  actively  associ- 
ated with  the  hobby  for  any  appreciable 
length  of  time  has  around  the  shack  a  multi- 
tude of  rigs,  rotors,  and  test  equipment 
which  requires  occasional  maintenance  of 
one  type  or  another.  When  the  equipment 
was  new^  the  last  thing  on  the  owner's  mind 
was  a  future  need  to  refer  to  the  instruction 
and /or  service  manual.  All  too  often  it  is 
tossed  into  a  comer  and  forgotten-  Comes 
the  day  service  is  necessary  or  a  sale  immi- 
nent and  the  manual  is  not  to  be  found. 

One  excellent  way  to  keep  this  valuable 
information  at  your  fingertips  is  to  place  all 
such  data  in  a  three-nng  notebook  (threes 
ring  because  smaller  manuals  will  still  be 
held  by  two  of  the  rings).  The  dime-store 
variety  binder  will  do  nicely.  While  there, 
also  buy  a  set  of  inexpensive  dividers^  and 
label  each  with  a  type  of  equipment.  Having 
separate  sections  fox  the  various  types  of 
equipment  will  speed  your  progress  when 
you  need  a  particular  manual. 

A  second  method,  which  I  find  to  have 
advantages,  is  to  buy  a  separate  folder  for 
each  piece  of  equipment-  The  cardboard 
type  with  three  double  metal  tabs  is  avail- 
able at  your  local  stationery  store  in  various 
colors-  In  this  shack  red  indicates  transmit- 
ters, black  is  test  equipment,  grey  is  anten* 
nas,  rotors,  and  other  outside  hardware.  A 
typed,  gummed  label  on  the  cover  indicates 
the  exact  contents.  These  folders  may  be 
neatly  kept  on  a  bookshelf  where  they  will 
be  easy  to  find*  The  uniform  size  and  the 
color  coding  make  the  shack  take  on  an  air 
of  neatness  which  could  well  become  con- 
tagious. William  P,  Turner,  W A0 ABI 


Solutio 

n  to  puzzle  on  page 

114 

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Dollar  Sale 

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P.O.  Box  78,  N.  Salem,  N.H.  03073 

LET  US  TRY  TO  HELP  YOU  WITH  YOUR  ENG  PROBLEMS 


122 


73  MAGAZINE 


Kn  igh  t 


V-107   VFO 


Two  Meters 


Just  finished  the  Knight-kit  V-107  VFO 
and  it  took  me  one  hour  to  do  it.  Would  you 
believe  two  hours?  Honestly  it  took  me 
three  hours  by  my  stop  watch  to  assemble, 
wire  and  calibrate  this  VFO.  Time  was  not 
essential,  but  I  was  anxious  to  see  how  long 
it  would  take  to  complete  the  kit  and  have  it 
operating- 
Assembling  the  Knight-kit  V-107  VFO  is 
so  simple  that  any  previous  experience  is  not 
necessary.  The  instructions  in  the  manual 
make  every  step  of  construction  easy  to 
follow.  The  text  and  pictures  show  exactly 
where  each  wire  or  component  fits  in.  Yes, 
the  wires  are  even  cut  to  length,  stripped  and 
ready  for  soldering-  \%  you  are  not  an  expert 
on  soldering  now,  there  are  some  exceUent 
lessons  in  the  construction  manual  which 
will  make  you  one. 

The  V-107  VFO  is  usually  sold  as  an 
accessory  for  the  TR-106  and  TR-108 
Knight-kit  Transceivers  but  it  can  be  used 
with  any  2  or  6  meter  transceiver  or  trans- 
mitten  It  uses  the  Clapp  oscillator  (some^ 
times  known  as  Colpitts)  for  maximum 
stability  and  has  a  high  L/C  ratio  in  the  tank 
circuit,  resulting  in  less  drift.  The  output  of 
the  VFO  has  a  minimum  of  20  volts  RMS 
which  is  enough  to  drive  most  any  trans- 
mitter for  the  2  and  6  meter  bands.  A 
high-gain  pentode,  I2BK6,  is  used  for  the 
oscillator  tube  and  a  voltage  regulator  tube, 
0A2,  is  used  to  stabilize  the  voltage  on  the 
screen  of  the  12DK6. 

Cahbrating  the  V-107  is  no  problem  if  the 
step-by-step  instructions  are  followed  in  the 
construction  manuaL  You  will  find  it  just 
takes  three  important  adjustments,  L-1,  L-2 
and  C-2,  to  calibrate  the  VFO  for  either  2  or 
6  meters.  With  these  adjustments  finished 
you  are  ready  to  work  anybody  on  these 
bands  and  be  on  frequency  of  any  station.  It 
might  be  suggested  that  these  calibration 
adjustments  be  made  after  a  thirty-minute 
warm  up  to  make  sure  they  are  correct. 


Ralph  Steinberg  K6GKX 
1 10  Aigonne  Avenue 
Long  Beach,  CA  90803 


Power  requirements  are  200  volts  DC  at 
30  ma  and  12.6  volts  AC  at  150  ma  for  the 
I2DK6  oscillator  tube  and  can  be  supplied 
from  the  TR-106  or  TR-IOS  Knight-kit 
Transceivers.  Should  the  VFO  be  purchased 
separately,  power  can  be  taken  from  the 
transmitter  or  transceiver  of  your  choice.  An 
outboard  power  supply  with  the  same 
voltages  win  do  as  well. 

When  the  V-107  VFO  was  finished,  "on 
the  air"  workouts  were  done  to  check  drift, 
temperature  and  mechanical  stability.  On 
drift  it  was  minor  and  in  line  with  the 
specifications  of  the  manufacturer,  AUied 
Radio  Corporation.  For  temperature,  it  was 
cool  as  cucumber  and  this  is  due  to  power 
levels  kept  at  a  minimum  allowing  for  very 
little  heat  dissipation.  The  mechanical  sta- 
bility can  be  said  that  the  V-107  is  mgged 
and  designed  hke  the  well  known  expres- 
sion .  •  .  ''just  like  a  battleship," 

Two  different  2  meter  transmitters  were 
used  for  checks  on  this  VFO  and  in  each 
case  there  was  plenty  of  drive  and  it  operated 
the  '*rigs"  satisfactorily.  Much  of  this  was  due 
to  keeping  the  output  cable  of  the  VFO 
short,  as  recommended  in  the  construction 
manual 

For  the  ham  that  has  just  a  few  crystals 
to  operate  on  the  2  or  6  meter  band,  the 
Knight-kit  V-107  VFO  just  cannot  be  beat  at 
the  price  of  $24,95, 

.  ^  .  K6GKX 
Technical  Specifications 

Frequency  coverage:  8.333  to  8.666  mhz  for  6M; 

8.000  to  8.222  mhz  for  2M. 

Frequency    stability:      +/-500   cycles   per   hour 

after   30   minutes, 

RF  output:    20  volts  rms  minimum  into  47K/30 

pf. 

Power  requirements:    200  vdc  ^  30  nia;  12.6  vac 

fe  0.15  amp. 

Tube  compliment:    12DK6  oscillator;  0A2  volt- 

age  regulator. 

Cabinet  size:    5Vr  x  4-5/16"  x  eVi". 


^ 


OCTOBER    1969 


123 


Careers  in   the 


Sam  Kelly  W6JTT 

12811  Owen  St. 

Garden  Grove,  CA  92641 


Looking  for  a  way  to  combine  a  career  in 
electronics  with  adventure  and  above  average 
earnings?  Want  exciting  work  on  a  tropical 
island,  a  tracking  ship  on  the  high  seas  or  in 
Europe?  If  so,  you  should  look  into  the 
opportunities  in  field  service. 

Field  service  (also  called  field  en- 
gineering) provides  technical  support  and 
operating  personnel  for  equipment  after  it 
has  left  the  home  plant.  As  you  can  guess, 
the  U,  S.  Government  is  the  biggest 
customer  for  electronics  equipment  and  field 
services.  The  government  needs  technical 
help  to  keep  the  vast  amounts  of  electronic 
equipment  associated  with  our  space 
programs  and  weapon  systems  operating. 

Besides  private  industry,  many  branches 
of  the  government  operate  their  own  field 
service  organizations.  An  example  is  the 
Federal  Aviation  Agency  (FAA).  The  FA  A 
maintains  an  excellent  field  service  organi- 
zation that  performs  such  widely  diversified 
tasks  as  making  radar  surveys  to  determine 
the  best  locations  for  long  range  radar 
stations  to  the  installation  and  check  out  of 
the    latest    digital    computers.   Many  other 


I  EC  Field  Service  Engineers  prepare  a  port- 
able telemetry  system  for  a  polaris  tracking 
mission  at  sea. 


government  agencies  operate  similar  services. 
Field  service  organizations  have  openings 
for  job  skills  ranging  from  engineers  to 
electronic  assemblers.  In  general  most  hams 
would  be  interested  in  becoming  engineers 
or  technicians. 

This  is  one  of  the  few  fields  where  a  man 
can  still  work  into  an  engineering  job  title 
without  a  degree  in  engineering.  However^ 
this  is  rapidly  changing.  If  you  are  planning 
on  becoming  a  field  service  engineer  you 
should  obtain  a  Bachelor  of  Science  degree 
from  a  recognized  engineering  school. 
Concentration  should  be  on  applied  en- 
gineering courses  rather  than  the  more 
theoretical  subjects.  A  Master*s  degree  is  just 
as  desirable  here  as  in  other  engineering  jobs. 
It  is  especially  important  if  you  later  decide 
to  change  to  '^in-plant*'  work- 
Requirements  for  field  service  technicians 
vary  between  companies.  In  general,  the 
higher  quality  organizations  require  two 
years  of  junior  coUege  electronics,  a 
technical  school  certificate^  or  advanced 
military  electronics  training. 

Completion  of  military  service  is 
advisable  for  all  field  service  positions  as  this 
provides  invaluable  experience  in  working 
with  military  personnel,  and  most  field 
service  organizations  deal  directly  with  the 
military.  In  addition,  most  companies  pay  a 
premium  to  men  who  have  received  training 
in  armed  services  schools  on  equipment 
related  to  their  products. 

The  current  demand  is  greatest  for 
personnel  with  backgrounds  in  telemetry 
systems  and  metric  radar,  particularly  those 
with  experience  In  the  uhf  range.  This  is  due 
to  the  big  change  in  telemetry  frequencies 
from  the  old  215  -  265  mhz  band  to  the 
1435-1540  mhz  and  2200-2300  mhz 
bands.  Other  critical  areas  are  radar  repair 
and  digital  data  systems- 
Field  service  work  may  be  any  where  in 
the  world.  As  an  example  lEC,  the  prime 


124 


73  MAGAZINE 


FA  A  Field  Service  Techn^cfans  aligning 
UHF  receiver  banks.  In  addttion  to  on-the- 
job  training,  the  FAA  provides  exceMent 
classroonn  instruction  at  the  FAA  Academy. 

contractor  fox  POLARFS/POSEIDON  test 
instrumentation  has  operations  in  Spain, 
England  J  Guam  and  at  shipyards  in  the  U.  S. 
In  addition,  they  supply  personnel  and 
equipment  for  special  operations  on  ships 
throughout  the  world.  Men  in  organizations 
of  this  type  learn  to  move  fast.  Frequently 
they  have  to  be  at  a  new  location  thousands 
of  miles  away  overnight.  This  type  of  work 
demands  the  development  of  tremendous 
versatility.  One  job  may  be  trouble  shooting 
the  latest  S-band  telemetry  system  on  a 
tracking  ship,  the  next  may  be  installing 
missile  test  equipment  on  a  nuclear  sub- 
marine. 

A  well-known  field  service  organization  is 
PhUco-Ford's  Educational  and  Technical 
Service  Division*  This  organization  grew  out 
of  the  famous  **Tech'Rep"  group.  They 
currently  have  operations  throughout  the 
world,  from  exotic  pacific  islands  to  Viet 
Nam,  The  services  range  from  operating 
missile  test  ranges  to  running  mess  haUs! 

How  do  you  find  out  about  job  openings 
in  field  service?  Probably  your  best  source  of 
information  is  the  Sunday  edition  of  the  Los 
Angeles  Times.  Other  sources  are  the  trade 
journals  such  as  the  IEEE  Spectrum  and  the 
Engineering  Opportunities  magazine- 
Remember,  most  big  electronic  companies 
have  field  service  divisions.  A  letter  to  their 
personnel  offices  will  usually  bring  you  a  list 
of  their  openings. 

There  is  a  wide  range  in  the  quality  of 
field   service  organizations.  Some  are  little 


better  than  hiring  halls  for  semi-skilled 
technical  personnel-  Others  provide  men 
capable  of  doing  advanced  engineering.  It 
pays  to  carefully  investigate  before  accepting 
employment.  The  company^s  name  isn*t 
always  indicative  of  the  quality  of  their  field 
service  branch.  Arrange  to  talk  withr  per- 
sonnel working  in  the  organization,  and  visit 
one  of  their  facilities,  if  at  aU  possible.  In 
general,  the  smaller  the  company  the  greater 
the  variety  of  work  available  -  and  the 
greater  the  individuafs  responsibility. 

There  are  many  ''pros  and  cons"  to  field 
service  jobs.  In  the  asset  column  you  have 
travel,  adventure,  the  challenge  of  working 
on  a  wide  variety  of  state  of  the  art 
electronic  equipment,  working  with  inter- 
esting people  and  high  pay.  On  the  hability 
side  you  have  extensive  travel,  complicating 
your  family  Ufe,  high  living  costs,  wierd 
climactic  conditions,  and  high  pressure 
work.  If  you  are  looking  for  adventure  and 
are  single,  the  habilities  are  quickly  over- 
come! The  pay,  which  is  above  average, 
helps,  and  in  most  instances  there  is  an 
additional  tax  free  per  diem  allowance  of 
from  $12  to  $25  per  day, 

. .  ,  W6JTT 


au^ 


OFFERS 


FROfA 
STOCK 

A  COMPLETE  LINE  OF 

nr- 

VERTICAL  ANTENNAS 

MODEL  IBAVQ  .  .  .  A  highperfor- 
mor»ce  all-band  vei-tical*  Autornatk 
bond  switching  oll-bondi   10  thru  80 

meters.  Feotar«s  irvdi vidua] Jy  tun«d 
Hy*Q  trops  that  provide  peobced 
performance  on  each  band.  Takei 
maximum  legal  power.  Feeds  with 
52  ohm  coax.  SWR  less  than  ?:1 
on  all  bands.  Simple  to  instoll  on 
ground  or  rooftop.  Withstands  100 
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Modef    1BAVQ'U7.5Q    NET 

OTHER   MODEL    VERTICALS 
IN    STOCK. 

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12AVQ  10,   15  &  20  Meters     $26,95 

ALSO  CHECK  WITH  US  FOR  OTHER 
HYGAIN    PRODUCTS, 


18AVQ 


i 


OCTOBER    1969 


125 


-1 


continued  from  page  7 

agers,  I  frequently  find  that  they  have  no 
desire  at  all  to  make  money.  This  may  be 
apathy  or  it  may  be  a  reaction  to  parents 
that  idolized  money.  It  is  frustrating  though 
to  have  wliat  seems  to  me  to  be  a  really 
simple  way  to  almost  unfailingly  make  a 
fortune  and  find  that  no  one  is  listening. 

How  long  do  you  think  it  will  really  be 
until  we  have  space  stations  parked  in  our 
skies  making  wires  across  the  earth  a  thing  of 
the  past?  Telephones  in  the  shirt  pocket.  FM 
radio  and  TV  from  space.  Instant  accounting 
down  to  the  smallest  store  in  the  country. 
Letters  and  photo  copies  anywhere  instant- 
ly. The  hardware  and  software  for  this  boom 
will  be  manufactured  by  new  companies, 
and  hams  will  play  an  important  part.  The 
youngsters  that  recognize  this  now  and  get 
ready  for  it  wiU  be  the  winners.  Ham  radio  is 
an  excellent  start.  And  courses  such  as 
advertised  by  Cleveland  Institute  can*t  but 
help* 

It  might  be  inspirational  for  the  younger 
members  of  your  radio  club  if  you  invited 
some  of  the  older  members  who  have  used 
their  background  in  ham  radio  and  parlayed 
it  into  success  to  give  a  talk.  If  you  don*t 
have  any  real  success  stories  in  your  club^ 
look  around  your  local  area  and  you'll  find 
them. 

Much  of  the  hard  work  they  will  tell  you 
about  and  which  is  a  key  ingredient  of  their 
success,  is  education.  It  may  not  be  in 
college,  but  it  could  be  self-education^  read- 
ing, mail  study  courses,  and  brain-picking 
every  expert  you  can  corner. 

Before  you  sit  down  to  write  a  heated 
letter  hating  me  for  discussing  such  out- 
rageous ideas,  please  take  some  time  and 
marshal  your  facts,  I  will  bow  to  documen- 
tation  and  facts,  not  to  steam  and  emotion 
based  upon  disturbed  beliefs.  As  always,  1 
will  most  enthusiastically  publish  further 
thoughts  along  this  line,  pro  or  con. 

Reactionaries 

The  next  time  you  run  into  someone  on 
the  air  or  at  a  club  meeting  that  gets  mad 
when  you  try  and  discuss  methods  of  im- 
proving the  ARRL,  just  remember  that 
reaction  is  a  very  normal  human  condition. 
The  human  body  tends  to  reject  the  trans- 


plant of  foreign  tissue  on  it.  This  certainly  is 
rather  parallel  to  the  way  in  which  any  mind 
tends  to  reject  any  idea  which  seems  un- 
fa miliar  or  wliich  threatens  an  existing 
system.  The  intrusive  forces  are  sloughed  off 
or  ignored,  just  as  an  aging  Hon  tamer  resists 
the  decision  of  a  circus  manager  to  buy  more 
lions,  or  just  as  an  executive  tends  to  resist 
the  decision  to  computerize  a  business, 
forcing  him  to  grow  into  new  skills. 

Ideas  must  be  presented  slowly  and 
cautiously,  always  equating  them  to  pre- 
viously understood  concepts,  if  they  are  to 
be  accepted.  It  is  all  too  easy  to  leap  into  a 
conversation,  as  I  frequently  do,  presenting 
the  solutions  to  problems  rather  than  the 
groundwork  for  understanding  the  problems, 
which  wlU  in  turn  lead  to  the  obviousness  of 

the  solutions.  Don't  do  as  I  do,  do  as  I  say: 

Marathon  Nets 

Bud  Massa  W5VSR  has  been  registering 

some  legitimate  complaints  about  the  over- 
bearing arrogance  of  some  net  control  opera- 
tors. His  letters  are  inflammatory,  so  Til 
digest  the  complaint  for  you.  The  problem  is 
that  some  net  managers  have  gotten  the  idea 
somewhere  that  the  net  frequency  is  sacro- 
sanct and  that  everyone  should  move  off  the 
frequency  when  it  comes  net  time.  After 
using  a  certain  frequency  for  some  months 
or  years  they  have  developed  the  strong 
belief  that  this  is  now  their  frequency. 

As  a  strong  believer  in  the  value  of  nets,  I 
recognize  that  they  serve  several  very  useful 
functions.  First  of  ail,  by  making  it  conven- 
ient for  a  group  of  similarly  interested 
operators  to  get  together  they  make  amateur 
radio  more  fun  for  all  involved.  I'm  all  for 
tills.  Secondly,  by  stacking  a  large  number  of 
stations  all  on  one  frequency  with,  normally, 
only  one  talking  at  a  time,  gjeat  gobs  of 
frequencies  that  might  otherwise  be  used  are 
conserved-  I'm  all  for  that,  too. 

There  is  no  question  that  it  is  a  lot  more 
difficult  to  run  a  floating  net  than  a  fixed 
one.  When  the  qrm  is  heavy,  it  can  be 
awfully  hard  to  locate  a  net  if  it  is  even  a 
khz  off  its  regular  channel.  Most  of  the  time^ 
tliis  really  isn't  true,  and  the  gathering  could 
easily  take  place  plus  or  minus  5  khz  with 
little  difficulty. 

Perhaps  a  Uttle  more  consideration  from 
everyone   concerned   will  smooth  over  the 


126 


73  MAGAZINE 


p 


problem  before  it  gets  to  the  FCC  petition 
stage.  Net  managers  could  make  a  try  at 
starting  on  the  net  frequency  and,  if  resist- 
ance develops,  could  ask  the  fellows  using 
the  channel  to  direct  net  call-ins  up  or  down 
a  few  khz  to  a  clearer  channel.  Four  years 
ago  I  was  given  the  stiff  arm  by  the  net 
control  of  the  YLRL  net  and  I  am  still 
resentful.  Let*s  try  real  hard  not  to  have  this 

continue, 

FCC  Actions 
RM-1455    is   a   request   for   the   FCC  to 

return  to  its  previous  practice  of  issuing 
requested  amateur  radio  calls,  when  avail- 
able, when  sufficient  reason  exists  for  their 
issuance.  It  proposes  that  similar  calls  be 
issued  to  amateurs  changing  call  areas.  Thus 
WIXYZ  could  request  and  receive  W2XYZ, 
if  available,  upon  moving  to  the  second  call 
area. 

With  roughly  one  fifth  of  the  amateurs 
moving  every  year^  it  would  be  nice  if  we 
could  return  to  the  old  FCC  custom  of 
permitting  the  retention  of  the  call  suffix 
when  changing  call  areas.  Please  drop  a  letter 
to  the  FCC  backing  this  proposal  so  we  can 
maintain  our  call  letter  individualities. 

RM-1456  is  a  request  for  the  Technician 
licensees  to  be  granted  the  same  A-1  oper- 
a  ting  privileges  as  the  Novice  Licensees. 
Since  the  only  difference  between  the 
Technician  and  the  Novice  License  is  the 
theory  exam,  there  would  seem  to  be  as 
much  value  in  the  Tech  having  the  same 
opportunity  to  learn  CW  by  practice  on  the 
air  as  the  Novice.  Since  few  VHF  receivers 
are  capable  of  receiving  CW,  the  Techs  are 
robbed  of  the  use  of  code*  We  might  see 
many  more  of  them  going  to  the  General 
Qass  License  if  they  were  not  bottled  up  on 
voice  bands. 

Please  write  to  the  FCC  and  give  them 
your  thoughts  on  this  matter,  FCC,  Washing- 
ton, D.C.  20554-  Only  one  copy  is  required 

for  comments  on  RM's. 
FCC  Pronouncement 

Since  the  fall  amateur  contest  activity  will  soon 

be  here  J  we  believe  you  will  be  interested  in  a 
resume  of  a  recent  explanation  of  what  the 
Commission  considers  to  be  an  acceptable  station 
identification,  as  follows: 

For  comphance  with  rule  Section  97.87(a),  the 
last  transmission  of  the  exchange  of  transmissions 
with  another  station  must  include  that  "other" 
station's  call  sign-  For  example  "BK  589  CAL  TU 


DXIDX  de  W6XYZ  K"  would  be  in  compliance 
with  §97 •87(a).  When  there  is  a  need  for  identifi- 
cation of  the  "other"  station  in  an  exchange  for 
the  benefit  of  our  monitoring  facilities,  it  is  most 
likely  to  be  heard  if  it  is  in  the  last  transmission  or 
at  the  end  of  a  long  single  transmission. 

Where  the  transmissions  of  an  exchange  are 
very  brief,  such  as  the  typical  contest  exchange,  if 
it  is  less  than  30  seconds  duration,  the  entire  last 
transmission  is  considered  the  '*end  of  the  ex- 
change" for  the  purpose  of  compliance  with 
§97. 87(a)*  Provided  there  is  no  mistaking  which  is 
the  transmitting  station's  call  sign,  the  call  signs 
may  be  anywhere  in  such  last  transmission.  While 
the  rule  no  longer  gives  examples,  continuation  of 
the  traditional  practice  of  placing  the  transmitting 
station's  call  sign  last  or  preceding  it  by  "de'*  is 
acceptable  for  this  purpose. 

Examples  of  acceptable  end-of~exchange  trans- 
missions of  less  than  30  seconds  are: 

^^DXIDX  de  W6XYZ  589  CAL  BK" 

"DXIDX  W6XYZ  589  CAL  K'* 

*'DX1DX  589  CAL  de  \V6XYZ  r* 

*'DX1DX  589  CAL  W6XYZ  K'' 

'^589  CAL  DXIDX  W6XYZ  K" 
For  telephony,  the  voice  equivalent  of  the  fore- 
going examples  may  be  used,  substituting  ''this  is" 
or  "from"  for  "de",  etc, 

ARRL  Questionnaire 

Some  $37,000  has  been  quietly  spent  by 

the  League  General  Manager  out  of  a  fund 
set  aside  several  years  ago  for  the  inter- 
national protection  of  amateur  radio.  Are 
the  members  of  the  League  entitled  to  any 
accounting  of  this  substantial  expenditure? 
Usually  reliable  sources-tell  us  that  a  good 
part  of  these  funds  have  been  used  for 
pleasure  junkets  for  top  HQ  officials.  Who  is 
responsible  for  accounting  for  these  funds? 
Has  there  been  any  evaluation  of  the  inter- 
national status  of  amateur  radio  or  of  the 
effect  that  the  spending  of  this  $37,000  has 
had?  When  something  like  this  is  kept  a  tight 
secret  it  is  only  natural  to  worry  that  there 
may  be  a  cover-up  of  skullduggery. 

The  stockholders  of  most  corporations 
insist  on  knowing  where  the  money  goes. 
They  demand  to  know  the  salaries  of  the 
officers  and  want  nothing  hidden  from  them 
in  the  published  financial  statements.  ARRL 
members  have,  for  many  years,  been  asking 
for  the  same  basic  information  about  their 
club,  but  with  no  success  whatever:  The 
truly  impressive  salaries  at  HQ  are  highly 
classified  and  subject  only  to  conjecture, 
even  by  staff  members*  If  the  salaries  axe 
reasonable,  then  why  this  tight  secrecy? 
What  is  being  hidden?  Wayne 


OCTOBER    1969 


127 


ZL  to  SM  Moonbounce 

John  ZLIAZR  arranged  schedules  with 
Kjell  SM7BAE  during  early  1969,  but  the 
very  short  overlap  of  mutual  moon  visibility 
made  it  difficult.  Times  and  frequencies 
were  worked  out,  with  144.003  mhz  being 
selected.  The  antenna  would  have  to  be 
pointed  witMn  2^of  the  moon.  "On  our  first 
sked  on  March  3rd  we  heard  each  other  at  a 
just  detectable  level.  The  next  day,  at  1728 
GMT,  call  signs  were  partially  copied  and  at 
1746  signals  peaked  to  12-15  db  above  the 
noise.  In  the  next  few  minutes  call  signs  and 
signal  reports  were  exchanged  to  comply 
with  the  accepted  standards  required  to 
constitute  an  official  contact. 

"The  total  useful  period  was  about  eight 
minutes,  the  moon's  elevation  was  9^ and  we 
think  that  the  extra  3-6  db  ground  reflection 
gain  due  to  low  angle  radiation  greatly 
assisted/' 

SM7BAE  ran  1500  w  to  a  4CX250R  and 
16  ten  element  yagis.  The  receiver  used  a 
2N4416  preamp  up  at  the  antenna,  ZLIAZR 
ran  a  pair  of  4-40 O's  in  Class  B  with  about 
600  watts  output  and  eight  bays  of  6/6  slot 
fed  yagis.  The  receiver  had  a  preamp  up  at 
the  antenna, and  a  bandwidth  of  some  200 
cycles* 

The  signal  report  system  used  was  a  code 
containing  the  letters  T,  M  and  O,  T  means 
that  weak  signals  are  present,  M  means  that 
partial  call  signs  are  being  copied.  O  means 
that  both  the  call  signs  and  signal  report 
have  been  copied*  If  almost  perfect  copy  is 
possible  the  number  ''5"  is  used.  Dots  are 
hardest  to  copy,  so  dots  are  only  used  in  the 
signal  reports  when  good  copy  is  probable.  A 
contact  may  be  claimed  if  an  O  level  is 
achieved. 

The  distance  involved  was  1 1 ,370  miles,  a 
Uttle  better  than  Ray  VK3ATN's  10,417 
miles, 

John  tells  us,  **There  is  no  easy  way  with 
moonbounce.  Anyone  deciding  to  have  a  try 
must  be  prepared  to  stop  being  a  communi- 
cator and  become  an  experimenter/' 

The  above  information  is  from  the  Journal  of 
the  Aukland  VHF  Group^  via  Amateur  Radio,  the 
Jownal  of  the  WireleBs  Institute  of  Australia, 


Boy  Scout  Jamboree-On-The-Air 

October  18-19 

Held  since  1958,  the  Jamboree-On-The- 
Air  (JOTA)  has  become  one  of  the  most 
popular  events  on  the  annual  scouting  calen- 
dar. Like  scouting  itself,  the  JOTA  has 
grown  from  what  in  1958  was  just  an  idea  in 
the  head  of  Les  Mitchell  G3BHK  to  an  event 
which  every  year  attracts  some  3000  stations 
in  over  70  countries,  each  with  its  own  little 
group  of  Scouts,  Cubs  and  Guides.  Some 
stations  have  as  many  as  150  Scouts  atten- 
ding during  the  48  hour  event. 

Apart  from  its  main  object  in  promoting 
friendship  between  the  boys,  the  JOTA  does 
have  one"  other  major  aim— that  of  intro- 
ducing boys  to  amateur  radio.  It  is  interest- 
ing to  find  that  several  hundred  bOys  have 
ob tamed  their  own  amateur  licenses  as  a 
direct  result  of  being  exposed  to  our  hobby 
for  the  first  time  during  the  JOTA.  Some  of 
them  are  known  to  have  gone  on  and  made 
their  careers  in  electronics  and  allied  fields. 

On  a  world  wide  basis  the  JOTA  is 
organized  by  the  Boy  Scouts  World  Bureau 
which  was  untU  early  1969  located  in 
Ottawa,  and  whose  permanent  station 
VE3WSB  became  a  most  sought  after  stat- 
ion, not  only  during  the  annual  week-end  of 
the  event,  but  also  during  Jamborees,  Ex- 
hibitions, etc.,  to  which  it  was  transferred  by 
special  arrangement. 

In  May  1968  the  World  Bureau  was 
transferred  to  Geneva,  While  awaiting  the 
completion  of  their  permanent  homCj  the 
directors  have  gratefully  accepted  the  offer 
of  the  use  of  4U1ITU  for  the  1969  JOTA, 

Thanks  to  the  Bulletin  of  the  Swiss  Union  of  Short 
Wave  Amateurs  for  the  above. 


If 


Up  with  miniskirts!" 


Moving?  Please 
Let  Us  Know! 


128 


73  MAGAZINE 


Scan 


nin 


the  Flyers 


Cart  Drumeiler  WSJ  J 
5524  NW  5Sth  Street 
Oklahoma  City,  OK  73122 


I  Scanning  H  &  R/s  Catalog  35 

I  Herbach  and  Rademan  catalog  volume 
35,  number  3  hardly  can  be  classified  as  a 
"bargain  sheet"'  in  the  usual  sense  of  the 
term.  It  does,  however,  provide  the  widest 
selection     of     high-quality    electronic    and 

I  mechanical  gear  you  can  find  anywhere  .  •  , 
and  often  at  much  reduced  prices.  As  cus- 
tomary, this  catalog  leans  heavily  toward 
laboratory-grade  goods.  Some  of  the  items 
are  used,  but  all  are  in  top-class  condition. 
Meter  multiplying  resistors,  at  0.5%  accuracy 
and  standard  capacitors  at  0,5%  accuracy  are 
examples  of  components.  There  is  page  after 
page  of  General  Radio,  Hewlett-Packard, 
Tektronix,  and  other  laboralory-type  equip- 

F  ment.  These  are  not  cheap.  For  the  amateur 
constructor,  tliere's  a  0-400  microam meter 
with  a  needle  movement  from  right  to  left 
.  .  .  just  the  item  for  a  signal-strength  meter 
in  the  plale  circuit  of  a  tube.  Another  choice 
article  is  a  miniature  200-0-200  microampere 
meter,  zero  center,  that  mounts  with  a  single 

t'A-inch  panel  hole.  This  should  be  handy  for 
a  discriminator  or  a  phase  meter.  The  first- 
listed  is  priced  at  $3.00,  the  other  at  $2.00, 
For  a  permanent  shop  set-up  you  can  buy 
(for  $15.00),  mounted  on  a  black  anodized 
aluminum  panel,  2-inch  Weston  meters:  O-I 
ma  dc,  0-5  kv  dc,  0-500  v  dc,  0-20-100  ma 
dc,  0-1  50  V  a c.  If  you're  interested  in  stable 
frequency  standards,  how  does  this  strike 
you?  A  500  khz  crystal  oscillator  with  a 
two-stage  harmonic  amplifier  for  S5.00;  the 
crystal  is  in  an  oven  which  requires  6,3  v  at  1 
a;  the  oscUlator  and  its  amplifier  need  105  v 
at  10  ma. 

Scanning  tlie  Radio  Shack  No.  189  Flyer 


I 


A  new  bargain  llyer  always  makes 
interesting  scanning.  This  one  is  no 
exception.  Several  unusual  ''buys''  catch 
your  eyes  immediately.  Like,  for  instance, 
lO-watl  resistors  in  fractional-  and  low-ohm 
values     such     as    are     needed     for     power 


transistor  emitters:  these  are  two  for  79^. 
Their  aluminum  ^*mini'^  boxes  are  both 
inexpensive  (H^)4  to  $L29)  and  adaptable  to 
many  a  hamshack  project. 

It  seems  that  most  projects  involve 
transistors.  And  transistors  often  are  happier 
if  you  use  a  heat-sink  when  soldering  to  their 
leads.  At  99^  for  a  kit  of  five,  you  can  buy 
peace  of  mind  inexpensively,  especially 
when  you  consider  that  one  of  the  five  has  a 
magnetic  base  that'll  often  provide  that  third 
hand  which  nature  failed  to  provide  to 
electronic  experimenters. 

Although  the  designers  probably  didn't 
have  amateur  radio  in  mind,  the  "Servo- 
Switch"  ($14,95)  can  be  used  to  good  effect 
by  many  operators.  It  comes  in  two  units, 
both  of  which  plug  into  the  AC  power  line. 
One  unit,  the  receiver^  sets  adjacent  to  the 
device  you  want  to  turn  on.  The  other  is  a 
transmitter  that  you  can  take  into  any  other 
pyrt  of  the  house.  If  you  want  to  watch  a 
TV  program  right  up  to  the  minute  you're 
due  on  a  schedule,  you  watch  it.  But,  about 
ten  minutes  before  "air  time/'  you  snap  a 
switch  on  that  little  hand-held  transmitter 
.  ,  .  and  on  comes  your  rig. 

The  69^  packets  of  small  hardware  are 
hard  to  pass  up.  It  seems  that  youVe  always 
short  of  some  small  item.  With  28  to  choose 
among,  most  of  your  needs  can  be  met. 

Scanning  World  Radio  Lab's  Catalog 

This  catalog  is  unique  in  at  least  one 
respect:  It  is  the  only  one  that  starts  out 
with  amateur  radio  gear  and  then  drifts  into 
CB  and  audio  equipment!  And  what  a 
welcome  relief  it  is. 

In  another  matter,  too,  it  is  higlily  unu- 
sual. That  relates  to  the  wide  variety  of 
amateur  equipment  lines  it  lists.  You  might 
think  Leo  would  push  his  own  excellent  line 
(Galaxy)  to  the  exclusion  of  others.  Not  so- 
You'll  find  Swan,  Drake,  Sideband  Engi- 
neers,   Jolinson,    Ameco,    Gonset,    Millen, 


I 


^ 


OCTOBER    1969 


12!? 


Waters  J  HaUicrafters,  Collins,  National,  Ham- 
mar]  und,  Sonar,  and  a  few  other  but  lesser- 
-known  brands  given  quite  complete  cover- 
age. The  prices  are  right,  too.  Like  many 
other  dealers,  you'll  find  ''discounts"  (a  very 
naughty  word  among  manufacturers  and 
many  dealers)  hidden  under  the  guise  of 
inflated  "trade-in"  allowances.  These,  of 
course,  apply  only  in  instances  of  purchases 
of  higher-priced  items.  Most  dealers  consider 
themselves  fortunate  if  they  don't  have  to 
pay  too  much  to  have  traded-in  equipment 
hauled  off  to  the  city  dump;  so  they  can 
take  this  loss  only  when  there's  a  consider- 
able profit  on  the  sale. 

This  catalog  lists  quite  a  number  of  items 
that  you  can't  find  easily  elsewhere-  Open- 
wire  transmission  lines,  copperweld  antenna 
wire,  guy  wire,  three-gang  capacitors  for 
pi-networks,  coils  and  switches  for  pi-net- 
workSj  and  (hold  your  hats!)  ferrite  beads! 
Another  item  seldom  seen  is  a  miniature 
rotary  switch  that  has  a  progressive  shorting 
feature  ,  ,  ,  a  very  desirable  capability  in 
some  applications.  Another  rare  one  is  an 
adapter  to  mate  a  male  uhf  connector  to  a 
female    Type    N    connector;    this    for  just 

From  the  stand-pomt  of  a  really  complete 
listing  of  manufactured  amateur  trans- 
mitters, transceivers^  and  receivers,  plus  a 
reasonably  good  listing  of  components  for 
amateur  building  projects;  I  conclude  that 
the  World  Radio  Laboratories  catalog  is  one 
of  the  most  valuable  available. 

Scanning  the  Poly  Paks  Flyer 

Bargain  hunters  are  getting  a  glassy  look 

in  their  eyes  -  .  ,  that  new  Poly  Paks  catalog 

has  just  too  many  attractive  "buys"  to  keep 

track  of  them.  You  can  pass  over  page  one, 

>ut  page  two  lists  a  1 .5  A,  2000  PIV  diode 

or  just  $1.00;  it  ought  to  hold  just  about 

my  power  supply  for  modern  transceivers, 

'age    four    shows    a    Fairchild    703    linear 

ntegrated  amplifier  for  $1,59.  That's  hard 

o  beat.  Across  on  page  five,  you'll  see  a  23 

/   NPN  transistor,  rated  to  400  mhz,  for 

2.99.  At  that  amount,  one  can  afford  to 

idulge  in   frankly   experimental    '"cut  and 

ry"  exploration  in  the  field  of  transistorized 

ransmitters.   Page   six   is  a  happy  hunting 

round.  There  you'll  find  15-olim  earphones 


at  4  for  SI -00;  SOOO-ohm  ones  at  2  for 
$L00.  Handsome  instrument  knobs  are  5  for 
$1.00  in  the  2'*  size  and  3  for  $K00  in  the 
3"  .size.  These  are  for  !4"  shafts.  The  back 
cover,  reaUy  page  eight,  shows  2N2222  NPN 
transistors  at  5  for  $L00,  Considering  that 
these  are  good  for  a  half -watt  dissipation, 
can  stand  up  to  60  volts  or  take  up  to  800 
ma  (but  not  both  at  once),  and  work 
satisfactorily  art  250  mhz;  yoi^'d  be  hard  put 
to  come  up  with  a  better  source  of  oscilla- 
tor, multiplier,  and  buffer  stage  transistors. 

Scanning  the  Allied  Summer  Flyer 

Like  many  flyers,  tliis  one  tends  more 
toward  completed  items  of  consumer's 
goods  rather  than  components.  Nevertheless, 
it's  of  interest  to  the  avid  bargain  hunter. 
Leafing  tlirough  it,  the  first  thing  to  perk 
your  interest  may  be  tlie  $10  price  reduction 
of  the  Model  A-2515  solid-state 
communications  receiver,  which  makes  it  an 
even  more  desirable  item  to  have  around  to 
supplement  your  amateur-bands-only 
receiver.  Overleaf  is  an  i^M-FM  receiver  for 
$8-88,  This  triggers  a  thought:  Why  not  a 
converter  feeding  into  this  for  a  nearly 
no-cost  50  mhz  or  144  mhz  FM  receiver? 
(More  on  tliis  later,) 

Now  for  some  components.  Twelve  heat 
sinks  for  popular-size  transistors  for  just 
$1.78  looks  like  a  real  bargain.  So  does  a 
transformer  having  6.3-V  and  65-V  (center 
tapped)  secondaries  for  only  9%4\  this  Is 
nearly  .ideal  for  transistor  experimentation. 
A  wide  range  of  zener  dioded  at  two  for  68^ 
(1  to  2  W  rating)  suggests  inexpensive 
voltage  regulation  for  tbat  power  supply. 
And  there*s  a  crystal  microphone  for  %%i\ 
Remember  what  they  used  to  cost  30  years 
ago? 

Let^s  get  back  to  that  converter-plus-FM 
receiver  combination.  This  begins  to  look 
even  more  interesting  when  you  read  over 
the  specifications  for  the  $29,95  Model 
KG -2 20  receiver  kit.  This  has  all  the  goodies 
that  would  cost  you  time,  effort,  and  money 
if  you  were  to  build  your  FM  receiver  from 
scratch-  Ft  has  a  ratio  discriminator  (none  of 
this  slope-detection  makeshift),  squelch,  and 
slow-motion  tuning.  Its  metal  cabinet  should 
provide  some  measure  of  sliielding,  if  you 
were  to  use  it  as  a  tunable  if.  Having  both 


30 


73   MAGAZINE 


r 


tubes    and    transistors,    you*d    have    power 
available  for  either  type  of  converter. 

A  simple  crystal-controlled  converter  for 
either  50  mhz  or  144  nihz  should  be  easy  to 
design  and  construct.  For  local  signals,  one 
dual-purpose  tube  would  do  the  job.  Or,  if 
you're  really  ambitious,  you  could  come  up 
with  a  converter  that  would  break  the 
squelch  on  a  one-microvolt  signal! 

Scanning  the  Olson  #769  Catalog 

Olson  is  a  firm  that  issues  catalogs  at 
rather  frequent  intervals;  therefore  each  edit- 
ion differs  but  little  from  the  previous  one. 
Catalog  #769  lists  the  usual  lines  of  imports, 
mostly  useful  gadgets,  but  few  items  relating 
directly  to  amateur  radio.  Of  course,  cr>^stal 
microphones  at  two  for  one  dollar  will 
attract  the  attention  of  any  amateur  who 
works  phone.  And  if  that  amateur  has  a 
phone  transmitter  without  VOX,  he  may  be 
interested  in  spending  $14,95  for  a  hand- 
held microphone  with  a  built-in  six-transis- 
tor VOX  circuit.  As  no  anti-VOX  is  provi- 
ded, he  may  have  to  keep  his  receiver 
volume  low  or  wear  headphones  to  avoid 
chattering.  Another  useful  item  is  a  circuit 
breaker  that  may  be  used  on  everything 
from  low-voltage  dc  to  117-volt  60-Hz  ac. 
These  may  be  had  for  1,  5,  8  or  20  A  at 
prices  ranging  from  $2.99  to  S3.49. 

.  ,  ,  W5JJ 


Errata 


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T .  s-i; 


BUFFER 


_A_ 


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-O  +Sv 


03 


1 

OZ  ! 

2M2907     I 


tOOK 


IN645 


tu  .T^C 


^SlNE  WAVE 
OUTPUT 


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GND 


This  was  left  out  of  the  article  on  page  88 
of  September-    Please  cut  it  out  and  stick 

it  in. 


VHF  COAXIAL  ANTENNA:  all  brass  com- 
plete with  4ft.  RG  5S/U  coax.  Tuned  to 
VHF  Aircraft,  2  meters  and  can  also  be 
trimmed  to  other  freq.  ....  only  S2;95  ea. 

FACSIMILE  TRANSMITTING  CONVER- 
TER: Converts  facsimile  subcarrier  AM  to 
subcarrier  FM.  Output  connects  directly  to 
microphone  input  of  VHF  AM  or  VHF  FM 
transmitters.  New  with  diagram,  can  be 
used  with  teletype   *  ,  ,  , .Si 9.95. 

EARPHONE  WITH  SWINGAWAY  BOOM 
MIKE;  combination.  H63  .  .  only  S3.95  ea* 

CRYSTAL:  lOOOkc  for  LMor  BC221  $4.95ea. 
200  KC S1.49ea. 

2  METER  TRANSCEIVER  SPgClAL:  compact 

7"x8"x12".    QutpiiE    7    watti.    irtdudes  dyria 
motQr  Si   modulatcjr  with   10  channel  cryslaJ 
turj-ei;  all  in  [his  little  package. 
2  for  S36.00  or  SI 9. 95  each 

SPECIAL: 

5"     SCOPE:      MANUFACTURED     BY 
HYCON  Reconditioned  . . .  each  S75,0Q 

New. ...each  100.00 

HYCON  COLOR  BAR  GENERATOR 

Reconditioned each    65.00 

R'l  1  LATE  TYPE  Q5er  .....  each    12.95 

TRADE  ONLY 

TDQ  2  METER  Transmitter  also  RCK  com- 

pan  ion  receiver,  both  trade  value  (5150,00) 

MITE    Teletype    (cost   S3500.00   new)    with 

solid  state  supply,  compact  and  overhauled 

.,,.,..  (trade  value  S250.00) 

TEKTRONfCS  531    SCOPE  with  pfug  in,  in 

good  condition (value  $530.00) 

MODTL  28  ASR  Teletype  (trade  va!ue  $750) 
Tektronicsmodel512  less  case  (trade  value $175) 

X  J*  Glass  Electronics  Co. 

1 624  S.  Main  St.,  Los  A  ngeles,  CA     9001 5 


ALUMINUM 
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for    uhf  -  vhf 

Ideal  for  mounting  industriat,  com- 
mercial, citizens  band,  amateur,  or 
television  'receiving  antennas.  Ex^ 
ceptional  strength  in  proportion  to 
weight  quatities.  Easy  access  to 
equipment  mounted  on  the  Micro* 
fleet  top  mast  extension. 


Other  features  are: 

•  10  to  120  feet  high  in  easy  to 
erect  10  foot  sections. 

•  Available  factory  assembled  or 
in  kit  form. 

•  Lightweight  all  aluminum  10  foot 
sections  weigh  only  W/z  'bs. 
Low  maintenance,  will  never  rust 
or  require  painting, 

•  Staggered  ladder  treads  for  easy 
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1 


OCTOBER    1969 


131 


i^ 


m^m 


Houtf)  jTorum 


Ralph  Irace  WAIGEK 
Assistant  Editor ,  73 
Peterborough,  NH  03^8 


Today's  youth  has  been  speaking  out  all 
over  the  world  as  it  has  never  before  in 
history.  The  protests  are  heard  in  colleges 
and  even  high  schools.  The  pressure  is 
building  up  and  perhaps  we  can  look 
forward  to  some  explosions  in  amateur 
radio  • 

Youth  has  been  getting  the  dirty  end  of 
the  stick  from  the  ruling  cliques  in  many 
amateur  radio  clubs.  In  others,  and  more 
usually,  they  drop  out  in  disgust.  Bad  scene 
either  way. 

The  rumble  of  discontent  has  been  rising 
steadily  at  ARRL  conventions  and  the  day 
may  not  be  far  away  when  something 
breaks.  The  youth  are  well  aware  of  the 
dirty  deal  they  have  been  getting  from  the 
entrenched  old  timers  who  are  running  the 
League.  They've  watched  the  ARRL  Incen- 
tive Licensing  scheme  eat  dangerously  into 
the  ranks  of  the  youngsters  and  they  are 
angry  over  the  new  two  year  wait  for  a 
higher  class  license.  They've  watched  the 
FCC  figures  showing  a  catastrophic  drop  in 
newcomers  to  our  hobby  and  they  point  an 
accusing  finger  at  ARRL  HQ, 

The  rigged  ARRL  Open  Forums  at 
conventions  are  no  longer  fobling  the 
youngsters.  They  want  answers.  They  want 
action.  They  want  a  change  in  the  basic 
ARRL  policies  which  prevent  a  Novice  or 
Technician  from  holding  office.  They  are 
bitter  over  the  recent  change  in  the  by-laws, 
obviously  aimed  at  them,  where  the 
Directors  explicity  prohibited  anyone  under 
21  from  running  for  the  office. 


ED 

AN-URR-13  RECEIVERS 

225-400  mc/s  Needed  Urgently.  Highest  Pricas. 

Military  Electronics  Corp. 

11  Summit  Ave.,  E-  Paterson,  NJ  07407 

(201)  791-5050 


Have  you  run  into  an  SCM  that  refuses  to 
appoint  teenage  liams  to  leadership  posts 
(EC,  SEC,  etc.)?  If  you  run  into  this,  and  it 
is  not  unusual,  unfortunately,  then  get 
together  with  some  friends  and  try  and  get 
the  rascal  out  of  office*  Let  him  know  that 
you  care.  If  you  round  up  the  teenage  votes 
you  could  well  win,  because  many  of  the 
older  hams  are,  sunk  into  disinterest  and 
could  caie  less  even  if  the  hobby  continues. 
They  may  be  dead  from  the  neck  up,  but 
you  aren't  and  you  can  run  rings  around 
them. 

Teenage  traffic  nets  are  fun  and  informa- 
tive.  They  are  a  step  in  the  right  direction. 
There  are  only  a  handful  at  the  moment, 
such  as  the  New  England  Teenage  Net  which 
meets  daily  on  3905  at  1900  EDT,  The 
Missouri  Teenage  Traffic  Net  meets  Monday 
through  Saturdays  on  3904  at  1900  CST, 
The  Cornhuskers  (Nebraska)  Teenage  Traffic 
Net  gets  together  daMy  on  3982  at  1830 
MST,  The  Tennessee  Teenage  AM  Net  works 
Monday,  Wednesday  and  Fridays  on  7280  at 
2200  EDT,  If  you  know  of  more  nets  please 
tell  me  about  them* 

We  really  do  need  a  lot  more  teenage 
nets,  so  how  about  getting  things  started  in 
your  area  and  passing  along  the  word  to  me? 
We  could  even  use  a  national  teenage  net  if 
some  of  you  want  to  bite  off  a  really  big 
chunk  to  chew  on.  Sound  groovy?  Ahright, 
write  to  me. 

In  the  meanwhile,  how  about  making  a 
big  try  at  getting  some  teenagers  into  the 
SCM  chairs.  Do  you  realize  that  not  one 
single  SCM  in  the  entire  74  ARRL  sections  is 
a  teenager?  It  is  really  about  time  that  the 
teenagers  got  into  gear.  It  takes  only  five 
signatures  from  ARRL  members  to  run  for 
SCM,  you  know.  Don't  let  them  keep  you 
down  forever  ,  .  ,  give  them  a  battle  this 
year! 

...WAIGEK 


^ 


132 


73  MAGAZINE 


DUAL  TRANSISTOR   IGNITION  SYSTEM 


f 


h 


Mw  f4iM«  *t»m* 


This  system  was  made  by  Canadfan  Tire  to  sell 
for  $35,00.  These  are  Brand  New  fully  wired 
surplus,  not  reiects.  The  extra  high  voltage  coil 
provides  smoother  running  at  high  speeds  and 
longer  plug  life,  and  the  lower  current  through 
the  points  makes  for  longer  point  life  and  faster 
winter  starts.  Special  connector  allows  instant 
change  over  to  conventional  ignition.  Fully  Guar- 
anteed, with  instructions  ready  to  install  for  6  or 
12  volt  negative  ground  car.  CLOSE  OUT  SPECIAL 


POOR   MAN'S   HI   Ft  HEADPHONES 


The  Canadian  Air  Force  has  surplus  also  and  we 
were  fortunate  to  obtain  over  500  headsets  from 
them  and  are  passing  the  savings  on  to  you. 
They  are  unused  and  in  the  original  cartons.  The 
headphone  efements  are  actually  miniature  speak- 
ers, as  pictured,  and  this  fs  the  way  Hi-Fi  phones 
are  constructed.  Will  give  excellent  fidelity  with 
either  voice  or  mustc.  They  have  rubber  pads 
with  chamois-type  covering,  metaf  headband,  cord 
and  plug.  4  to  16  ohm  impedance  for  use  with 
any  radio  or  TV,  etc.,  by  attaching  to  the  speak- 
er leads.  May  be  converted  to  "stereo"  by 
making  connections  at  each  ear  phone.  This  is 
a    real    bargain   for  quality   RCAF  head   sets. 

rVwA'T  ^4  1^  PH.— T-n....  — ,1 ■      I   ..  ■■■rT ■r^^H-m^wr'^-3   *\J\J  fP  ■   ^  P 


X 


m 


=  5  " 


GSe  C$9.50 


UNIVERSAL  LOGIC  CIRCUIT  CARDS 


GOVT  SURPLUS-EQUIPMENT  CASES 

Cast  Afunninum  case  with  handle  and  rubber  feet. 
Threaded  bosses  inside  provides  means  of  fastening 
Items.  Toggle  clannps  provided  for  ease  of  opening 
case.  This  rugged 
m  i  1  i  tary  case 
measures 
13"x12"x9" 
deep.  This  case 
will  give  that  pro- 
fessional look  to 
your  projects. 
This  case  will 
scrap  out  at  over 
$5.00  &  cost 
$80,00  to  manu- 
facture. QTY. 
LTD. 
Shipping  wt.  30  lbs. 


Instant 
logicl-!4 

for 

10  pin 

TO-5 


illllliilMt 


or 

14   lead 

dual 

In-line 

INTEGRATED   CIRCUITS 

These  boards  are  the  most  useful  Items  we  have 
ever  offered  for  breadboarding  with  low  cost  in- 
tegrated circuits.  The  cards  are  made  from  1/16'' 
G  10  Glass  Epoxy,  with  pads  for  14  lead  dual  in- 
line mounting  pads  on  one  side  and  10  lead  TO-5 
pads  on  the  other.  8  lead  TO-5  cans  will  mount 
rn  the  !0  lead  TO-5  pads  also.  Discrete  Tran- 
sistors  and  components  can  be  mounted  in  the 
locations  between  the  LC.'s,  power  supply  leads 
are  already  routed  around  the  board.  Our  com- 
petitors charge  $9.50  each  for  circuit  card  and 
mating  connector.  We  give  you  a  surplus,  un- 
used px.  board  with  components  on  it  (that  you 
can  keep  for  your  junk  box),  a  connector  and  its 
mate,  and  our  great  circuit  card.  You  drill  out 
the  desired  hole  pattern,  unsolder  the  connector 
from  the  surplus  card  and  install  it  on  the  new 
card,  wire  in  the  LC.'s  and  compute.  A  few 
minutes  of  your  time,  and  you  save  over  80% 
of  the  cost  of  comparable  p.c*  cards.  Get 
enough  for  your  breadboarding  needs  now  be- 
cause these  are  going  to  go  fast, 
2  Cards  &  mating  connectors 


10  Cards   &  mating  connectors 


2   ICCC 

$  2-50  p,p. 
10   ICCC 


$10,00  p.p. 
100  Cards   &   mating  connectors   100   ICCC 

$88.00  p.p. 


TELEG 


ER'S  TYPEWRITER 


These  Gov't  surplus  standard  manual  UNDER- 
WOOD typewriters  with  11"  carriage  will  gfve 
your  messages  that  authentic  RTTY  look.  Last 
time  we  offered  these,  we  were  sold  out  in  three 
weeks.  Only  25  available.  Pin  feed  type,  but 
easily  converted  to  regular  type  by  changing 
roller.  Mill  key  board  in  good  condition. 
Shipping  wt.  50  lbs,  UTT  $29.50 


SEND  2%c  FOR  OUR  LATEST,  BEST  CATALOG 
YET,  JAM  PACKED  WITH  ELECTRONIC  BAR- 
GAINS    ,     -     .     FREE     WITH     AN     ORDER     -     .     . 


Enterprises 


p.  0.   BOX  44,   HATHORNE,    MASS.  01937 


OCTOBER    1969 


133 


LETTERS 


bear  Wayne, 

I  believe  your  honorable  draftsman  made  a 
small  erroT  in  the  ^*u!tra  stable  power  supply" 
diagram  on  page  116.  The  IK  resistor  ought  to  be 
in  the  '*down"  lead  from  the  +300  volts;  the  low 
voltage  end  of  the  IK  then  goes  to  solid-state  VR 
and  to  plate  of  Vl-B. 

Neil  Johnson  W20LU 

74  Pine  Tree  Lane 

Tappan,  NY  10983 

Dear  Wayne, 

^"The  Genesis  of  Radio  Reception"  by  WIUSM 
in  Aug.  73  was  most  interesting,  as  it  contained  the 
technical  information  on  early  radio  expeiiments 
that  history  books  always  leave  out. 

Bill  Hood's  excellently  written  article,  however, 
makes  no  mention  of  the  American,  Nathan 
Stubblefield,  who  is  certahily  not  an  unknown.  On 
the  contrary,  Stubbleficld  must  be  rated  as  the 
most  inventive  and  advanced  of  the  radio  pioneers. 
In  1892,  he  demonstrated  his  apparatus  which 
could  send  and  receive  voices  and  music  at 
distances  of  at  least  a  mile  over  land  or  sea.  He 
even  built  smalU  portable  rigs  that  equalled  or 
bettered  the  performance  of  today's  economic 
marvel  of  Japanese  technology -the  three  transistor 
walkie  talkie! 

This,  mind  you,  was  happening  several  years 
before  Brardy  learned  how  to  make  iron  filings 
fidget  in  his  '*coherer,**  many  years  before  the 
electron  tube  or  thej:rystal  diode,  and  quite  a 
while  before  the  eighteen  year  old  Marconi  would 
become  famous  with  his  crude  spark-gaps  and 
"conveyor-belt"  receivers. 

I  would  certainly  like  to  see  some  information 
on  the  circuits  and  equipment  used  by  Nathan 
Stubbleficld,  the  apparently  forgotten  inventor  of 
modern  radio  communication, 

J,  R.  Johnson  WA5R0N 
5111  Boca  Raton 
Dallas,  TX  75229 

Dear  Wayne^ 

After  reading  your  recent  editorial  about  the 
ARRL  proposing  to  give  away  ten  meters  to  the 
CB  gang  I  went  on  the  air  and  tried  to  get  some* 
letters  going  to  the  Directors.  Out  of  25  contacts 
only  three  said  that  they  would  write.  The  others 
said  it  sure  was  terrible,  c  u  agn  sn  sk. 

Bussed  Piatt  WA9ZVD 

126  Laura  Lane 

Thornton,  IL  60476 

Dear  Wayne, 

In  reference  to  my  letter  published  in  the  May 
issue,  I  would  like  to  thank  the  many  hams  for 
their  letters  and  cards.  Everyone  received  was  in 
accord  with  my  remarks  on  the  incentive  licensing 
issue  that  was  forced  on  us  by  the  ARRL  and  the 
FCC 

As  I  continue  to  observe  the  results  of  this 
insidious  incentive  licensing  rule  I  see  how  it  will 
have  continuing  cumulative  psychological  effects 
that  will  be  detrimentak 


Most  hams  that  do  get  the  Advanced  and  Extra 
Class  fmd  a  coolness  towards  them  when  they 
begin  to  mention  it  over  the  air.  The  majority  seem 
to  feel-well  so  what,  now  stay  in  your  exclusive 
part  of  the  band  and  don't  bother  us,  there  is 
enough  qrm  around  without  your  type.  So  I 
suggest  to  the  amateurs  that  wish  to  waste  their 
time  and  money  taking  tlie  Advanced  and  Extra, 
keep  quiet  about  it.  Just  remember  the  ham  on  the 
other  end  may  feel  as  I  do  that  you  have  let  your 
fellow  hams  down- they  are  sitting  this  one  out 
because  they  feel  it  is  a  stupid,  senseless, 
undemocratic  and  unfair  ruling  that  will^  if  given 
enough  time  and  is  ignored  by  the  majority  of 
sensible  thinking  hams,,  be  rescinded  as  it  was 
before  for  what  it  is -useless  and  a  waste  of  our 
band  allotment. 

I  suggest  hams  contemplating  Advanced  and 
Extra  give  the  above  serious  consideration.  I  would 
ratlier  keep  all  my  friends  than  be  thought  of  as  a 
superior  big  brain  and  resented. 

1  sometimes  wonder  if  this  was  not  instigated 
for  the  express  purpose  of  reducing  the  ranks  of 
the  amateurs  in  the  United  States.  Could  this  be 
the  amateur  pill? 

One  of  the  truths  of  warfare  is  to  divide  and 
conquer.  They  have  certainly  divided  the  amateurs, 
scared  off  many  a  newcomer  and  disgusted  many 
an  old  timer  into  hanging  up  Ms  key. 

George  Brook  Taylor  W4PZS 

1 133  S,W- Fifth  Place 

Fort  Lauderdale,  FL  33312 

Wayne, 

This  is  just  a  letter  from  a  member  of  the 
younger  generation  who  feels  that  while  everyone's 
telling  everyone  else  to  run  a  ham  radio,  he  might 
as  well  throw  in  his  two  bits. 

The  credit  for  my  original  interest  in  amateur 
radio  goes  to  Walker  Thompkins  K6ATX.  As  a 
twelve  year  old  in  need  of  a  book  report  1  read  his 
adventure  story,  "SOS  at  Midnight''  and  got  so 
excited  about  it  that  1  read  his  other  books,  '  CQ 
Ghost  Ship**  and  '*DX  Means  Danger/  of  my  own 
free  will.  After  following  the  books*  hero,  Tommy 
Rockford  (16  year  old  electronics  genius,  footbaU 
player^  detective,  and  superhero-K6ATX), 
through  many  exciting  adventures,  I  had  learned  a 
lot  about  fiam  radio  and  1  was  eager  to  become  a 
ham.  As  IVe  always  thought  that  1  was  a  normal 
twelve  year  old,  I  will  surmise  that  other  twelve 
year  olds  can  be  equally  impressed  with  Tommy 
Rockford  and  ham  radio. 

Attention  hams  and  ham  clubs!  Be  certain  that 
K6ATX's  books  or  books  like  them  are  in  every 
grade  school  library.  But-make  sure  that  in  every 
book  is  an  insert  giving  names,  addresses,  and 
telephone  numbers  of  amateurs  in  the  area  who  are 
willing  to  help  people  get  started,  or  willing  to  just 
show  a  wide-eyed  youngster  a  ham  shack.  1  could 
have  become  a  ham  five  years  ago  when  I  read 
"SOS  at  Midnight/'  but  I  didn't  make  myself 
known,  and  local  hams  didn't  make  themselves 
known. 

Duane  McGuire 

933  Crescent  St* 

Raymond,  WA  98577 


*^ 


♦  ^j*t 


73  MAGAZINE 


I 
I 


Daar  Wayne, 

This  bait  store  is  located  about  a  mile  north  of 
HiUsboro,  Ohio  on  state  route  73,  hence  the  name 
"73  Bait,"  Mr.  D.  L.  Simpkins  is  the  owner  and  has 
given  permission  for  you  to  publish  the  picture  if 
desired. 

We  could  have  "doctored"  it  up  a  bit  with 
someone  posing  with  a  75S3  on  the  end  of  a  line, 
but  thought  that  tJiis  was  sufficient  to  get  the  idea 
across. 

Paul  Terrell,  MD  W8NT2 

1440  N.  High  St. 

Hillsboro,  OH  45133 

Dear  Sirs: 

I    noticed    the    two    following   errors   in    the 

printing  of  my  article  **4  Thirty  Twoer"  in  the  July 

issue  of  73.  In  figure  3,  the  catliode  pins  (pins  6)  of 

both  Vj  and  V2  should  be  shown  grounded.  Also, 

the  value   (riot  too   important,  however)   of  C7 

should   be   .001,   and  C2  and  C3  should  have  a 

maximum  value  of  20  pf.  While  this  may  seem 

trivial^  I  did  receive  a  long  distance  phone  call  from 

another  ham  who  wanted  to  know  the  capacitor*s 

values.  His  keen  interest  in  beginning  the  project 

overwhehned  me,  since  I  hadn*t  even  received  my 

copy  of  73  through  the  mail  yet! 

Larry  Jack  WA3AQS/KL7GLK 

3  Barry  Ave. 

^       ,^,  Annapolis,  MD  21403 

Dear  Wayne, 

Just  happened  to  run  across  the  article  ("Kluge 
Tube")  in  the  March,  1969,  issue.  As  I  (along 
with  a  few  other  hams)  was  deeply  involved  in  the 
development  and  mass  production  of  this  tube 
during  W1V2,  perhaps  I  can  shed  some  light  on  its 
characteristics  and  purpose. 

The  VT-158  was  the  brain-child  of  Dr.  (Major 
at  that  time)  Harold  Zahl  of  the  Ft.  Monmouth 
Signal  Corps  Laboratory.  It  is  essentially  a  304TL 
with  increased  filament  power  and  temperature 
(for  increased  emission)  and  with  rather  limited 
life  by  ordinary  standards. 

Although  the  internal  tank  circuits  may  look 
like  they  are  intended  for  a  frequency  of  lOOOmhz, 
the  operating  frequency  was  600mhz.  The  dif- 
ference being  due,  of  course,  to  the  internal  capaci* 
tances-  Mu  was^  like  the  304TL,  in  the  neighbor- 
hood of  ten.  Power  output  of  the  VT-158  was 
about  200  KW  peak,  at  an  input  of  approximately 
1  megawatt,  peak.  The  efficiency  wasn't  too  good, 
but  considering  high-power  triodes  at  this  frequen- 
cy, it  wasn't  too  bad,  either-  Operation  was  at  a 
plate  voltage  of  approximately  20kv  with  1  or  2 
microsecond  pulses  at   a  repetition   rate  of  240 


pulses  per  second.  The  pulse  modulator  was  a 
rotary  spark-gap  network*dischaige  device  attached 
to  the  shaft  of  the  gasoline-engine  driven  generator 
which  provided  power  for  the  whole  system.  The 
audio  output  from  this  spark-gap  outfit  was  deaf- 
ening, and  security  of  the  installation  must  have 
been  negligible. 

The  radar  system  employing  this  tube  was,  so 
we  were  told,  part  of  the  D-Day  invasion  appara- 
tus. Although  1  was  never  privileged  to  see  the 
complete  installation,  it  w^as  reported  to  have  been 
housed  in  a  tent  with  center-pole  mounted  para- 
bola* Its  mission  was  to  detect  low-flying  and  dive 
bombers*  As  I  recall,  the  prime  contractor  for  the 
system  was  W9ZN's  Zenith  Radio- 

R.  L.  Norton,  W6CEM 

722  East  Gutierrez  St.,  P.  O.  Box  1469 

Santa  Barbara,  California  93102 

Gentlemen: 

Recently  I've  run  into  some  "old  timers"  who 
would  like  to  get  back  on  the  air.  One  of  tlie  things 
that  seems  to  give  them  pause  is  the  new  termino- 
logy wMch  pervades  the  ham  magazines.  Modern 
electronic    magazines   are    written   only    for   the 
*^in'Crowd"  who  have  mastered  the  new  abbrevia- 
tions that  these  magazines  have  foisted  upon  them. 
Perhaps  1  can  be  of  assistance -=  here  is  a  list  of  these 
modem  abbreviations,  along  with  the  translation  of 
what  they  really  mean: 
pf  • .  •  not  a  sneaker -usually,  '*mickey  mice" 
/if .  , .  too  small  to  measure,  forget  it 
cap  ,  , ,  pronounced  ''condenser'* 
hz  ,  ,  .  pronounced  * 'cycles,**  with  one  exception- 
some   modernists  claim   that  **hz"  is  pro- 
nounced "Hertz,"  but  who  ever  heard  of  a 
"cycles  antenna"? 
khz  .  .  .  pronounced  "Kilocycles" 
ghz  .  • .  this  horrible-looking  glitch  is  the  excep- 
tion-say **kay-em-cee" 

ERP your  rf  ammeter  reading  times  at  least  50, 

PI  ,  - ,  a  magic  number  equal  to  (a)  exactly  3  or» 
(b)  exactly  the  square  root  of  10  depending 
upon  the  equation  in  w})ich  it's  used 
SWR 
VSWR    , .  .    swer   or  viz  war -this  you  ignore  in 

quoting  ERP -ignore  it 
FCC  .  - ,  means  the  same  old  thing- this  you  can't 

ignore! 

Doug  McGarrett  WA2SAY 

28  Holbrook  Road 

Centereach,  U  U,  NY  11720 

ITEMS  OF  TRIVIA 

Page  123-124  of  July  issue  appears  to  have 
diagrams  reversed -right?  When  1  took  my  1st  class 
telephone  test  almost  fifteen  years  ago,  one  of  the 
questions  involved  an  FM  discriminator  and  all  I 
could  remember  was  where  it  was  grounded.  Still 
remembering  only  that,  the  diagram  totally  con- 
fused me  until  the  text  tended  to  clear  it  up. 

Vm  sure  glad  you  stay  away  from  space-filling 
chatter  ("Operating  News")  as  one  of  the  other 
magazines  uses,  such  as  W6XXX  bought  a  new  call 
book,  or  WA3XXX  put  some  new  finals  in  his 
linear.  Seriously,  the  Pickering  Radio  people  have 
an  excellent  product  in  their  code  practice  tape, 
and  after  seven  weeks  of  intensive  work^  I  passed 


OCTOBER    1969 


135 


the  FCC  test.  The  Pickering  tapes  should  receive 
enthusiastic  endorsement.  (WA6CPP  passed  his 
advanced  exam  .  ,  . ) 

Paul  Schuett  WA6CPP 
14472  Davis  Road 
LodJ,  CA  95240 
Dear  Wayne, 

I've  been  reading  your  73  Magazine  editorials; 
and  I  like  your  frankness  and  open-minded  views, 
so  I'm  wTiting  to  express  mine. 

Just  a  little  background  so  we  talk  the  same 
language.  I've  been  interested  in  ham  radio  since  I 
bought  my  first  receiver  in  1933  for  $33.00. 
Twenty-seven  years  later  I  sold  it  for  $30.00  to  a 
young  fellow  trying  to  get  his  ticket,  and  it  worked 
like  new. 

Over  the  past  years,  Tve  belonged  to  several 
radio  clubs  and  have  helped  many  a  ham  get  his 
ticket  and  a  TVI  free  rig  on  the  air.  Why  not,  ham 
radio  has  been  and  still  should  be  the  best  hobby, 
and  it  is  a  good  investment  for  our  country.  You'll 
notice  I  said  has  been  and  should  be, 

I  consider  the  years  up  until  the  early  I960's 
the  Golden  Years  of  ham  radio.  Those  were  the 
days  of  home  brew  equipment  and  comradeship. 
Fifty  or  seventy-five  miles  was  not  even  considered 
wiien  it  came  to  helping  a  fellow  ham  de-bug  his 
rig.  The  accompUslunent  and  the  feeling  of  pride 
one  received  when  he  heard  "old  Virg's"  rig  on  the 
ail  made  ham  radio  have  a  meaning.  To  sit  up  half 
the  night  and  work  on  a  piece  of  equipment  while 
ragchewing  with  a  mobile  or  two  that  were 
following  the  local  H.  S,  or  college  team  bus  home 
through  a  storm  was  just  part  of  being  a  good  ham. 
Integrity,  responsibility,  and  justifiable  pride  were 
a  part  of  the  teaching  to  be  a  good  ham  that  was 
given  each  new  ham.  He  knew  if  he  did  not 
measure  up  he  would  be  dropped. 

In  the  early  60's  several  things  began  that  have 
changed  the  conditions  and  attitude  of  ham  radio. 
The  two  major  ones  were  the  introduction  and 
acceptance  of  CB  radio  and  SSB  ham  radio. 
Progress  is  inevitable  and  new  things  will  come  out. 
To  classify  or  not,  CB  or  SSB  as  good  or  bad  is  not 
really  the  issue,  as  both  have  their  good  and  bad 
points.  To  point  out  the  real  issues,  1  will  give  an 
example  that  happened  to  me.  Many  (too  many) 
similar  examples  have  happened  since;  and  1  got  to 
thinking. 

After  successfully  building  my  own,  mobile  and 
home,  AM  &  F  M  rigs  and  could  use  the  home  rig  as 
a  relay  station,  I  figured  F*d  try  SSB.  Some  surplus 
xtals  and  equipment  and  many  moons  later  I  had 
an  excellent  workable  rig  with  a  grounded  grid 
(4-I625's  parallel  on  75  mtrs,)  on  the  air,  TR 
switch  and  alL  My  first  contact  (outside  local)  gave 
me  a  good  report  at  first  but  when  we  exchanged 
Q-th  equipment  types  he  never  came  back.  Later 
(several  days)  I  heard  him  ragchewing  with  another 
station,  and  he  said  he  was  not  about  to  talk  to 
anyone  who  didn't  have  top  line  (no  commercial 
names)  equipment.  If  the  sigs  weren^'t  coming  in 
S-9+  he  wouldn't  even  answer  them.  As  1  said,  this 
happened  so  many  limes  to  me  that  I  began  to  say 
I  had  ''top  line""  equipment.  Then  I  really  started 
thinking.  Is  this  really  ham  radio? 

Where  had  my  integrity  and  pride  of  accomp- 
lishment gone?  This  is  not  the  ham  radio  for  me. 
So  projecting  a  long  took  far  into  the  future  ! 
could  see  only  one  workable  plan  to  keep  Iiam 
radio  alive  and  with  sometliing  to  look  forward  to. 
So  I  began  to  express  myself  at  clubs  and  on  the 


air.  Several  old  timers  were  with  me,  but  that  was 
the  support  I  got. 

About  this  time  CB  radio  was  blossoming  and 
(even  through  1968  this  is  still  happening)  young 
higli  schoolers  and  the  college  set  found  they  could 
get  on  tlie  air  for  $40  to  $100  mobile  or  fixed 
station  and  no  code,  not  even  an  exam  for  a 
license;  and  they  could  yak  away  to  anyone  in  the 
country.  The  cost  of  SSB  equipment  for  a  mobile 
rig  is  from  S300  to  $500  and  if  they  get  that  kind 
of  money  they  invest  it  in  wheels,  a  bomb  or  some 
sort,  and  then  maybe^  I  say  maybe,  a  CB  rig,  It'^s 
easier,  costs  less,  and  they  have  less  restrictions* 
They  can  even  get  a  65  watt  transmitter  for  around 
$50;  so  who  needs  ham  radio?  Facing  this  reality, 
how  does  one  go  about  getting  them  interested  in 
being  a  true  ham. 

One  young  (H.  S.)  feUow  purchased  a  SSB 
transceiver  and  before  he  had  it  paid  for  it  was 
obsolete  (pwr.  &  selectivity  wise)  and  his  trade-in 
would  be  a  lot  less  than  he  had  a  right  to  expect  so, 
he  operated  as  is.  Try  selling  ham  radio  to  some  of 
these  youngsters  and  they  may  go  so  far  as  to 
invest  in  a  novice  Tx  &  Rx  and  for  a  short  time 
they  enjoy  it;  then  they  find  the  temptations  and 
the  going  tough.  They  have  invested  in  low  power 
AM  equipment  and  have  a  hard  time  selling  \L 
They  key  up  and  get  a  2  or  3  word  per  min, 
contact  and  then  the  return  op  comes  back  with  10 
or  15  w.  p.  m.  and  they  get  discouraged  and  start 
tuning  up  the  bands;  and  soon  they  find  the  CBers 
are  having  a  balL  Knowing  most  of  them^  he  finds 
he  can  get  a  xtal  and  pur  his  rig  on  with  the  rest  of 
them.  Another  ham  lost. 

It's  not  hard  to  see  today's  problems,  or  mess, 
or  hangups,  or  what  ever  you  call  them,  they  are 
real  and  definitely  with  us.  So  once  again  Til 
propose  what  I  feel  is  a  solution  to  our  problems.  I 
know  ril  get  a  lot  of  static  but  then  I'm  used  to  it 
by  now* 

The  main  thing  is  to  think  for  the  good  of  ham 
radio  and  not  for  the  good  of  oneself. 

With  SSB  and  RTTY  proven  to  be  fast  and 
superior  to  CW  why  not  leave  OV  out  of  the 
picture  (except  as  a  rider).  All  hams  should  by 
exam  prove  they  know  theory  and  good  opera- 
tional practices.  AH  hams  should  be  general  class 
and  use  any  band  but  be  restricted  to  250  watts 
input  or  pep  power.  (No  more  spirating  of  power 
and  price  out  of  the  reach  of  the  junior  and  the 
overseas  ops,)  After  3  years  of  a  general  ticket  and, 
the  buUding  of  a  complex  workable  piece  of 
equipment  plus  an  exam  one  could  get  an  advanced 
ticket  that  would  entitle  him  to  put  a  kw  on  the  air 
on  any  band. 

Area  clubs  who  have  at  least  one  advanced 
ticket  holder  as  an  officer  would  and  should  be 
permitted  to  give  the  exams.  They  would  also  have 
the  responsibility  of  updating  the  hams  in  their 
area  and  of  policing  (if  I  may  use  the  word)  the 
same.  F  or  the  ham  to  again  be  looked  upon  as 
anything  but  a  nuisance  he  must  accept  the 
responsibility  and  let  those  who  can  perform  be 
the  liaison  between  the  FCC  and  the  ham.  The 
local  newspapers  are  supposed  to  be  for  the  good 
of  the  people  they  serve,  so,  why  not  have  local 
committees  or  representatives  to  approach  the 
local  hams  and  CBers  who  are  directly  violating  the 
rules  and  privileges  of  the  area  and  print  their 
name,  address,  and  call  in  the  local  paper  for  a 
week  or  so.  If  they  don't  conform  tlien  let  the  FCC 
designate  the  action  to  be  taken. 

Active   clubs  with  dues  and   a   place   to   use 


136 


73  MAGAZINE 


modern  equipment  are  a  must  as  technology  has 
adviiiiccd  beyond  the  stage  of  each  liam  owning  his 
own  test  equipment  or  of  (m  many  cases)  the  ham 
even  repairing  his  own  equipment.  If  we  don't  pull 
together,  we  wUl  be  (as  we  are  now)  pulled  apart. 
As  the  first  part  of  tliis  letter  explained,  hams 
had  a  sense  of  togetherness  that  comes  by  doing 
thing Ji  togetlicr,  especially  workinq  together.  We 
can  no  longer  push  the  "on''  switch  of  a  higli 
priced  piece  of  equipment  and  be  just  appliance 
operators-  If  all  we  put  into  ham  radio  is  money,  1 

t don't  think  we  can  expect  much  out,  I  was  always 
taught  the  things  worthwhile  in  life  came  from  the 
heart  and  only  the  heart.  All  else  jusl  comes  and 
goes. 
So  what  say,  feUows,  lets  put  a  little  heart  into 
ham  radio  and  once  again  make  it  a  worthwhile 
thing. 
^  Wayne,  I  know  that  you  and  the  rest  of  the 
staff  will  kick  this  around.  Hop  in,  the  band  is 
open, 

William  A.  Gardner  W8EAU 
5704  Decker  Road 
North  Olmstead,  OH  44070 
Dear  Sir: 

Why  doesn't  your  magazine  run  a  series  of 
articles  on  computer  and  binary  logic  as  applied  in 
Integrated  Circuits.  There  axe  very  few  hams  tliat 
can  boast  even  the  slightest  familiarity  with  com- 
puter logic  and  L  C/s*  It  would  be  nice  to  have  a 
series  of  educational  articles  of  the  same  quality  as 
the  "Getting  Your  Advanced  Class  License"  in  the 
past  and  now  the  "Getting  Your  Extra  Class 
License,"  Thank  you,  1  got  my  Advanced  License 
thanks  to  your  study  course. 

John  C.  Koning  WB6VQE 

4680  Crest  view  Drive 

Norco,  CA91760 

Sounds  like  a  loser  to  ma;  any  other  votes  on  this? 

* .  -  ed* 


Dear  Wayne, 

Glad  to  report  the  acquisition  of  the  "EXTRA" 
ticket  recently! 

Biggest  factor  towards  getting  it  was  the  great 
articles  on  obtaining  the  '^big"  ticket*  They  are 
written  so  the  "self-taught  guy"  can  grasp  it -no 
technical  terms,  (or  at  least  very  few)  very  expiana- 
I  tory,  and  really  "step  by  step.'  Other  magazines 
are  great  if  you're  in  electronics,  or  have  an  E,  E. 
degree  J  but  as  for  me-i  needed  some  '^plain  ol 
language"  descriptions! 

I  found  'em  in  the  articles  and  must  say 
"thanks  a  lot"  to  the  staffs  effort, 

R.J-  Renart  WB2AUF 

1 1 7-09  9  Ave. 

College  Point,  L-  L,  NY  11356 

Dear  Wayne, 

In  August  issue,  page  98,  on  output  section,  on 
leads  going  to  the  meter,  a  diode  was  left  out  (any 
small  diode)  for  the  rf  output  meter- 

Thought  Vd  bring  this  to  your  attention  before 
someone  else  did! 

Bill  Estick,  KOVQY 

2607  E.  13th 

Wichita,  KA  67214 
Deaf  Wayne, 

During  the  past  many  years  1  have  enjoyed 
amateur  radio  to  its  fullest  degree.  I  have  met  some 
of  tlie  tlnest  persons  in  amateur  radio -and  a  few 
of  the  others.  The  spirit  of  maxim  and  others  has 
carried  amateur  radio  for  decades.  Today  we  need 


WE  PAY  CASH 
FOR  TUBES 

Lewispaul  Electronics.  Inc. 

303  West  Crescent  Avenue 

AllandalCr  New.  Jersey  07401 


REGUL.  pWR  SPLV  For  command,  lm,  etc. 

PP-106/U:  Metered.  Knob  adjustable  90  270  v  up 
to  80  ma  dc,  also  setect  an  AC  of  6.3  v  5A,  or  12.6 
V  2^3  A  Of  28  V  2'/!  A.    With  mating  output  plug  & 

e\\  tech.  data,    Shpg  wt  5W - *-.- 19<50 

BARGAfNS  WHrCH  THE  ABOVE  WILL  POWER: 
LM-Cl  Freq,  Meter:  ,125  20  mhz.  .01%,  CW  or 
AM,    with    serial  matched    catib.    book,  tech.   data, 

mating  piug.    Checked  &  grtd* 57.50 

TS  323  Freq,  Meter:  Similar  to  above  but  20  480 
mh2,  ,001%.    With  data. 169.50 

TS-175    Freq.  Meter:    85-1000  mhz.  .  .  .  ,75,00 

A-R.C.  R11A:  Modern  Q  5'ef  190  550  khz...  12,95 
A.R.C.  R22:  540  1600  khz  w/tuning  graph,. .17.95 
A,R.C.  R13B:    108  132  mhz  w/tuning  graph.JZ7.50 

HI-SENSITIVITY  UHF  RECEIVER 

375-JOOO  mhz.  Stoddart  RFI  Meter  NM  50A 
with  pwr.  sply,  cords,  dipole  holder,  3  pair  dl- 
poles.  Input  50  ohms.  IF  60  mhz.  Band- 
width 1  mhz  at  370  and  L8  at  I  ghz  RF.  Image 
&  spurjous-response  reject,  better  than  40  db. 
Senstt.  as  a  2-terminai  tuned  voltmeter  is  10  uv; 
win  be  less  with  I -pair  dipole,  but  you  can  make 
an  array  to  bring  it  up.  If  the  voltage-attenua- 
tion calib.  charts  didn't  get  lost  it  would  be 
worth     $1,250     in    surplus,    $2,852    from     the 

factory    so    we   will    sefl    it    as  a  simple  re- 

ceiver  in  grtd-excel.  condition  for  only  ...  $275 

ULTRA  WIDE-BAND  RECEIVER: 
AN/ALR-5:  Late  postwar  AM/FM  Countermeasures 
rcvr.  Has  S*Meter:  variable  IF  Atten.  &  passband  (0.2  or 
2  mhz  rrom  30  mhx  center);  AF.  Video  &  Pan.  outputs. 
New,  modified  for  120  v  60  hr,  inclydes  new  (Method  II 
pack)  4-band  plug*ir  converter  .038-1  ghz.  4  Type-N 
plugs  automatically  select  carrect  ant.  as  bands  axe  swit- 
ched. Sensit.  at  -6  db  setting;  6*/i  uv  thni  132  mhz,  13 
thru  780  mhz  &  4SYi  at  I  ghz.  BRAND  NEW.  with  book 
&  mating  pwr-input  plug,  only -w,. .,...275.00 

VERSATILE  PLATE  &  FILAM.  TRANSFORMER 
Depot  Spares  for  SP-600-JX:  PrL  95/105/117/130/ 
190/210/234/260  v  50/60  hz.  Sec.  1:  305  0  305 
V,  150  ma.  Sec*  2:  5  v  3  A.  Sec.  3:  6.3  v  5A. 
Sec.  4:  7'/i  V,  3/4  A.  Sec.  5:  7%  v,  1%  A.  Leoend 
tor  pins  IS  plainly  merked.    Herm,  sea  led.,, *......  2*95 

FOUND!  A  NEAT  &  COMPACT  SCOPE  XFRMR! 

Freed  12691:  DAS  Loran  Spares,  supplied  5"  CR, 
plates  &  htrs.  Pri.  105-1  30v  50/60  hz.  Sec  s.  insul- 
5  kv  1490  &  1100  V,  5  ma:  390  0-390  V  1  00  ma; 
electrostaticaHv  shielded  6.3  v,  0.8  A;  two  2H  v,  2 
A.  Sec  s.  insuL  1  V>  kv:  two  6-3  v.  6  A;  5  v,  3  A,  27. 
V,  5  A  Case  5*4x5x7%.  With  diagram.  Shipped 
only  by  collect  REA  Express... ..-.^.>.. >.».-,,.2>95 

FAIRCHILO   SOLID-STATE   SCOPES  all  w/dual 
trace  plugins  25   &    50   mhz,   w/deiayed  time-base 
plug  ins,    w/books,    overhauled    &    grtd*       As    low 
as .-.„«,. • ,.»».., ....825.00 

We  probably  have  the  best  Inventory  of  good  lab 
test  equipment  in  the  country.  But,  please  do  not 
ask  for  catalogl  Ask  for  specific  items  or  kinds  of 
Items  you  need\  We  also  buyl   What  do  you  have? 


R.  (l.  GOODHEART  CO.  INC. 

Box  1220  GC,  Beverly  Hills,  Calif   90213 

Phones     Area  213    Off ice-272  5707 

Messages    275  5342 


4 


1 


OCTOBER    1969 


137 


ARCTURUS 


•  Color  focus  rectifiers,   14,000   PIV 
at  1  MA,  99i  each.  6.5  KV  -  79rf. 

:;  •Color  TV   yokes,  70^and  90^ type., 

\\  Fit  almost  all  sets  -  $10.95  each. 

•  1700  Transistor  types  -  39rf  each> 

•  DS-501,  2N27S  power  transistor 
types,  Cat.#349  -  G9i  each. 

•  HEP170,  Motorola  HV/Current 
epoxy  silicon  rectifiers^  2.5  amps  at 
1000  PIV  -  49rf  each. 

•  FuMy  *  transistorized  UHF  tuners. 
Fit  most  sets.  Cat.#UHF56?  ~  $4.95 
each. 

•  UHF  tuners,  1  tube  type.  Fit  most 
sets.  C3t.#UHF3  -  $3.95  each. 


Complete  listings  of  electronic  Items  at 
similar  bargain  prices  are  available.  Write  for 
our  latest  catalog.  Minimum  order  $5,00, 
plus  postage. 

ARCTURUS  ELECTRONICS  CORP. 

5a2-22nd  St.,  Union  City,  N  J,  07087.  Dept.  73 

Phone  201  *Ufy4  5568 


RADIO  BOOKSHOP 


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The  Tf  ansiftor  Radio  Handbook,  h^dboufid 
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Price?^  iri^  po^lpajd  in  USA.  Closeoui  of  $toclc,  one  of  «  kind, 
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a  regeneration  and  real  vital  vitamin  shots  to 
mamtain  tlie  privilege  of  amateur  radio  operation 
throughout  the  world. 

The  value  of  your  efforts  in  publishing  the 
magazine  '*73*'  is  of  tremendous  value  in  preserving 
amateur  radio  as  a  hobby  and  as  a  public  service- 
Many  of  us  are  grateful  to  you  and  to  your  staff 
for  a  job  well  done-but  one  that  must  continue. 

John  TracVf  WIGH 

49  Broadway 

Taunton,  MA  02780 

73  Editor, 

I  wish  to  express  my  thanks  and  congratu- 
lations on  such  a  fine  Advanced  study  course.  I  at 
first  tried  to  learn  from  another  well  known 
publication,  which  need  not  be  mentioned,  and  did 
notliing  but  memorize  the  answers  as  you  said 
would  and  did  happen,  I  am  now  using  your  Extra 
study,  but  because  of  the  asinine  2  year  wait  for  so 
called  experience  is  keeping  me  back  anotlier  year. 
Anyway  thanks  again  for  such  an  outstanding 
study*  You  should  publish  the  courses  under  a 
different  cover.  1  am  sure  you  would  have  a  great 
success  with  it. 

Robert  McGwier,  Jr.  WB4HJN 

P.  O-  Box  565 
GFove  Hill,  AL  36451 
Good  idea  . .  .ed* 

Dear  Editors: 

Congratulations  on  your  decision  to  cover  allied 
fields  with  separate  publications.  While  there  are  a 
great  many  hams  who  use  CB  radio  (to  good 
advantage),  and  many  who  follow  the  SWbroad- 
castSj  they  would  do  better  advised  to  subscribe  to 
magazines  in  their  fecial  interest,  I  do  not  wish  to 
hunt  through  SWL  or  CB  news  to  get  at  the  Ham 
articles.  And  those  with  one  of  the  other  special 
interests  should  not  be  so  burdened, 

I  recently  checked  an  issue  of  QST  and  found 
about  one  tliLrd  of  it  of  interest  to  me.  There  are  a 
great  many  Hams  who  are  interested  in  contest 
news,  organizational  matters  and  other  items  which 
do  not  appeal  to  me,  1  do  think  QST  does  a  fine 
job  of  covering  tliis  wide  area.  They  have,  however, 
fallen  victim  to  a  common  failing  of  such 
publications  (yours  excepted).  The  people  who 
write  about  articles  they  would  Uke  to  see,  but 
never  bother  to  write  that  letter.  Since  the  desired 
articles  are  usually  advanced  engineering,  the 
Editors  get  the  erroneous  impression  that  tlieir 
readers  all  want  it.  They  forget  that  they  must 
attract  more  readers^  and  they  necessarily  will 
come  from  those  just  starting. 

Your  study  courses  have  been  by  far  the  best 
*'Self  Help"  courses  I  have  seen.  With  the 
traditional  Q  &  A  approach,  there  is  too  much 
tendency  on  the  part  of  the  student  to  try  to 
memorize,  rather  than  fully  understand.  There  will 
always  be  a  demand  for  the  "quick  and  easy" 
memory  course.  From  this  poup  come  our 
appliance  operators,  although  many  do  go  on  to 
learn,  and  build. 

Lester  Utch  WB4HPB 

1248  Haven  Dr. 

Birmingham,  AL  35214 

Dear  Mr.  Green« 

Having  been  a  charter  member  of  your  institute 
of  amateur  radio,  and  followed  with  enthusiasm 
the  meteoric  rise  of  73  from  its  inception,  this 
letter  is  addressed  to  you  because  it  is  felt  that  it 


^ 


1 


138 


73  MAGAZINE 


I 


RG  196  AU  50  ohm  teflon  coaxial  cabie.  Outside  dism^ter  080"  RF 
loss  .29  db  par  fcjot  at  400  Mhi  Silver  plated  sftielding  and  conductor. 
Used  lor  intefnal  chassis  wirmg,  antenna  coupling^  RF  coupling  between 
stages,  etc.  Random  lengthf  fronn  35  foot  to  150  foot.  Colors:  block,  rad. 
brown,  bJue,  grey,  orang«,  Regular  price-  23^  p^r  foot.  Owr  price  bi  per 
foot  $3,00  per  100  ft, 

455  Khi  cersnrtic  filterj  type  BF-456-A.  These  filters  will  help  To  sharpen 
the  sfllectivFty  of  most  sei%  using  455  Khr  IP's.  Use  across  cathode  bias 
fesistor  in  pface  of  a  cepecitor.  or  In  rraniisiDrized  sets,  across  the  emitter 
bias  resistor.  Impedanca  is  20  ohms  at  4S&Khz,,  DC  resistence  is  infinite, 
fnrhpedence  increases  rapidly  as  you  feavc  455  Khz.  Pfen  your  own  LC 
filter  circuits  at  very  low  cost. 
10  for  $1.00  25  for  $2,00 

TOROID  POWER  TRANSFORMERS 

f  T  Z  This  toroid  was  designed  for  use  in  a  hybrid  F,M,  mobile  unit,  usirig 
3  single  8647  tube  in  the  RF  amp.  for  30  yvetts  output.  Schematic  in- 
cluded, 12  VDC  pri,  using  21N1554  s  or  equivalent.  Sec  #1  500  volts  DC 
out  at  70  watts.  Sec.  42  65  volts  DC  bias  Sec  #3  1,2  volts  AC  for 
filament  of  8647  tube  Sec  #4  C/T  feed  back  winding  for  2Nf  554's.  1  V*' 
thick.   2%':  die  $2.95  ea,  -2  for  $5.00 

§  T'3  Has  a  powdered  iron  core  and  is  buijt  like  a  TV  fly  back  transformer. 
Operates  at  about  800  CPS.  12V  DC  Pri.  using  2N442's  or  equivalent.  DC 
output  of  V/DBLR  475  volts  90  watts.  C/T  feed  back  winding  for  2N442's 

$2,95  ea.  -2  for  $5.00 
TRAMSFORMERS 

P7  n7  VAC  Pri  Sec.  #1  185  CAV  @  120  ma.  Sec  #2  6,3  VAC  @  4A. 
Double  Half  Sheit  Mail  Box  Type.   SX  146  type.  $2.75  ea.  -2  for  $5. 00 

P'9    117  VAC  Pri.  Sec,  I  900  VAC  @  300  ma.   Sec.  #  2  10O  VAC  @  lOma 
Bias    Sec.  #3  12  6  VAC  @  AMP.  Wt.  16Vj  lbs.  Double  Half  Shell  $4  50 

P-10  M7  VAC  Pri.  Sec,  #1  960  VAC  C.T,  @  160  ma.  Sec  ff2  425  VAC 
C.T  and  tap  at  100  VAC  10  ma  Bias.  Sec  #3  126  VAC  @  4.5A  Double 
Shell  fVTail  Boit  type.   Wt.  8^.  lbs.  $3.75 

Output  transformers,  all  types  59  cents  or  3  for  $1,50 

OT-1  Transistor  TO'3  Povver  Diamond..  Imp.  15  ohms  to  3.2  ohms  DC 
Res,  Pri.  ,6ohm.   Sec,  .3  ohm. 

OT  2     Pri    imp-  7000  ohm.    Sec  3-2  and  500  ohm  for  Phones  or  70  volt 
line  3  watts.    Full  shielded  Double  Half  Sheli. 
OT'3  Pri,  Imp,  SSOO  ohms.   Sec.  3.2  ohms.  SCI 22  type 

All  prices  FOB.  All  weights  listed  are  net,  Please  allow  for  packaging. 
Please  allow  enough  for  postage.    We  will  return  any  extra. 

TOWER 


1220-22  Villa  St..  Racine,  Wf  53403 


GATEWAY 

ELECTRONICS 

6150  Delmar  Blvd.,    St.  Lauis,  Mo.   63112 

314-726  6116 

BLOWER— Squirrel    Cage    (new)    t15    volts  AC 

4x4x3  50  GFM 

Shipping  wt.  2  lbs ...i- „„„.$      4.95 

SOUNDSCRIBER  24  hour  logging  recorder    * 

Shippmg  wt,  50  (bs....„ ....$350.00 

ARC    1     TRANSCEIVER    (good    for   2   meters 

AM)  50  channel  ex.  cond* 

Shipping  wt.  75  lbs...., ...$    30,00 

TAPE  CASSETTES^C-6G  (1  hour) 

Shipping  wt.  Vi  lb ...,.$      1.00 

C-120  (2  hour) 

Shipping  wt.  ¥2  lb ,. ,,$      2.00 

CO-AX      CONNECTORS-PL259      Male      con- 
nector. 

Shipping  wt.  %  lb..  .............„...„......$         .40 

SO-239  Female  connector 

Shipping  wt,  Vi  lb, $         ,40 

WESTON     METER    40-0-40    Micro-Amp    I'A'^ 

new— ideal    for    2-way  radio  alignment,  etc. 

Shipping  wt.  2  lbs $     J2,95 

12     VOLT    CENTER     TAPPED     TRANSFOR- 

MER-70     AMPS.     115     volts     AC     inputs 

7x5^^x634 

Shipping  wt.  35  lbs...., $      9.95 

12    VOLT    DC   to    115   VOLT  AC    INVERTER 

KIT— Transistorized— 200  watt  output  com- 
plete with  aH  parts,  case  and  diagrann. 

Shipping  wt.  25  lbs,.,..  „...$    18.95 

Polar   RELAY  — Mercury  wetted;  similar  to  the 

255 A  {direct  replacement) 

Shipping  wt.  2  lbs $      4,95 

Minimum  order  $5.00.  Sorry,  no  catalog  at  this 
time.     Write  for  specific  items.    Watch  for  our 

ads  in  73.   Stop  in  and  see  us  when  you're  in  St. 
Louis. 


from  the  all-new,  still  unpublished  "FM  Repeater 

Directory,"  which   is   updated   continuously  and 

published  quarterly  in  FM  Journal 

Ken  Sessions  K6MVH 

_        ..,  Editor,  FM  Journal 

Dear  Wayne, 

Yes,  quite  a  few  of  us  are  out  here  want  to  be 
able  to  use  more,  not  less,  frequencies.  Opening 
3650-3700?  Now  that  would  be  incentive  and 
would  give  us  all  a  lift.  I  know  that  my  operating 
has  dropped  off,  way  off,  since  last  November.  I 
find  myself  squashed  toward  the  high  end  of  the 
band,  hearing  how  great  it  is  back  on  the  low  end 
where  1  operated  for  the  past  19  years.  Yes,  open 
something  new.  It  certainly  would  cut  down  the 
QRM.  And  what  about  this  VHF  beacon  for 
WlAW?  What  good  is  that  going  to  do  me?  We  sure 
do  need  something  to  spark  up  amateur  radio,  but 
I  don*t  think  the  punishment  we  have  been  getting 
is  the  answer. 

John  W4AEQ 


Tell  Our  Advertisers 
You  Sato  It  in  73 

"If   your   nose  runs  and  your  feet 
smell,  you're  built   upside  down/' 


Radio  Amateur 
Emblems  engraved 
with  your  call  letters. 


n   CSold 
□    Rhodium 

cati  letters 
$5>00  Ea. 


n  Gotd 

□    Rhodium 

call  letters 
$5.00  Ea. 


All  itfustrations 
ar.  ciclual  size, 


D  Gold 
n  Rhodium 

call  letters 
$5.00  Ea. 


I 


I 

I 

I 

r 
I 

I 

I 

I 


I 


Rush  Order  To:  RADIO  AMATEUR  CALLBOOK,  Inc. 

Dept.  E.   925  Sherwood  Drive,  Lake  Bluff,  III.  60044 


J 


140 


73   MAGAZINE 


will,  at  least,  receive  some  kind  of  consideration. 

The  subject:  the  QRM  problem  and  crowding 
on  our  phone  bands.  It  is  time  we  press  for 
remedial  action.  Incentive  licensing  certainly  did 
nothing  for  this  problem.  At  the  crux  of  the  matter 
there  seems  to  be  a  glaring  inequity  in  the 
frequency  allocation  that  confines  the  U.  sL 
amateur  to  a  portion  of  the  phone  band,  wMle 
foreign  stations  have  full  freedom  of  the  range,  so 
to  speak. 

Late  callbook  figures  show  the  U.  S.  amateur 
total  to  be  near  290,000.  While  foreign  registra- 
tions, not  including  Russians,  are  near  137,000.  If 
we  are  the  greater  in  number,  and  confined  to  the 
area  of  the  North  American  continent  geographic- 
ally, why  should  we  be  penalized  for  our  numbers? 
Why  should  special  portions  of  the  phone  bands  be 
pre-empted  for  foreign  use? 

If  you  tune  across  the  American  portion  of  our 
plione  bands  on  most  any  weekend,  you'll  find 
something  that  pretty  well  borders  on  bedlam. 
While  tuning  the  foreign  portion  of  the  band, 
you*lI  find  vast  empty  spaces  there. 

At  the  time  these  frequency  allocations  were 
made  for  our  phone  bands,  our  numbers  were  not 
such  as  to  create  any  problem.  Today ^  even  with 
our  sophisticated  equipment^  the  frequencies 
available  are  not  adequate  for  the  prevailing 
demands. 

For  a  long  time  that  has  been  a  rather  taboo 
subject;  however^  it's  time  to  open  up  Pandora*s 
box  and  let  the  thing  out  for  an  airing. 

We^ll  never  get  our  share  unless  we're  in  there 
fighting  for  it.  It's  time  now  to  pick  up  the  cudgelj 
pen  and  microphone  to  join  in  a  combined  assault 
on  an  unfair,  outmoded  agreement's  bailiwick. 

W,  A.HanksWOKJ 
Tebbetts,  MO  65080 

Dear  Wayne, 

Congratulations  on  a  beautiful  issue  (August 
1969).  I  particularly  enjoyed  your  FM  articles;  the 
timeliness  of  73  in  covering  the  "in"  aspects  of  our 
hobby  never  ceases  to  amaze  me.  You  people 
always  seem  to  be  "right  on  top  of  it.*' 

Referring  for  a  moment  to  the  article^ 
"FM-Fun  Maker":  Lest  65,000  anxious  amateurs 
run  out  quick  and  buy  crystals  and  FM  units  based 
on  the  author's  stated  popular  frequencies,  I  think 
it  advisable  to  contradict  one  small  point.  The 
author  says: 

National  repeater  frequencies  are  52,80  in, 
52.72  out  for  six  meters  and  146.34  in,  146,76  out 
for  two  meters. 

Prospective  FM  operators  should  be  advised 
that  in  the  United  States  and  Canada  there  are  106 
repeaters  whose  output  is  on  146.94  mhz.  There 
are  only  29  repeaters  in  these  areas  with  output  on 
146.76.  For  my  money,  146,94  mhz  could  hardly 
be  considered  anything  other  than  THE  national 
repeater  output  frequency.  Also^  1  know  of  only 
two  six -meter  repeaters  in  the  entire  country  with 
an  output  of  52.72,  and  one  of  them  is  keyed  from 
two  meters.  But  there  are  18  with  an  output  of 
52-525  mhz. 

Like  many  otlier  FM'ers,  the  author  of  the 
above-referenced  article  obviously  does  not  Uke 
repeater  outputs  on  national  simplex  channels.  But 
he  can  hardly  change  the  facts  by  ignoring  them. 

As  a  miscellaneous  tidbit  of  nonessential 
information,  there  are  234  open-access  repeaters  in 
the  U.  S,  and  Canada.  Nearly  200  of  them  are  on 
two  meters.  All  information  given  in  this  letter  is 


HAMS!     DON'T  BUY  USED  TUBES 
COMPARE  OUR  PRICES 
FOR  NEW  TUBES 
RCA"fiE-EIMAC-AMPEREX-ETC. 

811A-4.75,  4-125A-27.50,  4-65A- 12.00, 
5R4GY-1.75,  807-1.75,  WE350(807)-1.25, 
4-400A^38.50,  813-20.95,  4X150A-19.95, 
4-250A-36.50,  4PR60B-55.00,  4CX250B-21.00, 
8236-13.25,  2E26-2.75,  1625(807-12v  fiO-1.50, 
417A-2,25'  404A-2.25,  6146-2,75,  6360- 
3.50,  2X2-.50,  OD3-OC3^.S0,  5879-1 ,75. 
5881-3.25,  WE-CV677  1000WATT  TETRODE- 
5.95,  EIMAC-MACHLETT  VT-158  1200-3000 
WATT  BOTTLE-READ  MARCH  1969  ISSUE  73 

HOW  GREAT  THIS  IS"$9,95  12V  20AMP  DIODE 
POWER  SUPPLY  (LESS  XFORMER)~4.95,  RCA- 
6-12  VDC  CONVERTER  DEL.  20AMP-12.95 
IDEAL  FOR  VOLKSWAGEN.  SEND  FOR  OUR 
LIST  OF  OVER  3000  TYPES  OF  AMERICAN, 
BRITISH  AND  EUROPEAN  IMPORTED  TUBES, 
[LARGEST  STOCK  OF  XMITTING  TUBES  IN 
THE  WORLD,  SEND  FOR  OUR  LARGE  PARTS 
CATALOG  (OUR  PRICES  ARE  THE  LOWEST  IN 
THE  USA). 

UNITED   RADIO  COMPANY 

56-A  FERRY  STREET 
NEWARK,  NEW  JERSEY  D7105 


BACK  ISSUE  GUNSMOKE  ! 

30^  count  'em  30,  stupendous  tremendous 
(more  handbooks  than  magazines)  fascinat- 
ing enormous  devastating  incredibly  ener- 
vating back  issues  of  7 3 ,,*,., •...,.•. 

ONLY  $5.00 

postpaid      worldwide 


Yes,., yes.. .yes., .here  is  a 
flolden  opportunrty  to 
Blow  your  mind  on  30 
back  issues  of  73.  You 
send  us  $5  in  negotiable 
securities,  cash  or  check 
and  we  will  send  you  an 
unbelievable  miscellany 
of  thirty  different  (ail 
different)  back  issues, 
alt  from  the  1960-1966 
era.  These  are  all  rare 
collectors  items.  Every 
one  could  likely  be  wo- 
rth a  fortune  to  you.  Who  knows,  you  might 
even  find  a  rare  January  1961  in  this  pile!  We 
don't  even  know  what  is  m  these  packages.  To 
keep  costs  down  we  have  had  these  magazines 
packed  tnto  sloppy  bundles  by  the  Chimps 
from  Benson's  Wiid  Animal  Farm  {nearby). 
Watch  out  for  banana  skins,  —if  you  want 
specific  issues  of  73  they  are  available  at  the 
low  low  (high)  price  of  $1  each.  Unless  we 
don't  have  them.  In  which  case  the  price  is 
higher.  —How  about  sending  a  bundle  to  a  DX 
friend?  Back  issues  of  73  are  worth  their  weight 
in  unicorn  dung  in  most  countries.  —Money 
received  without  a  shipping  address  will  be  used 
for  beer. 

73  Magazine    Peterborough    NH   03458 


OCTOBER    1969 


139 


Price — $2  per  25  words  for  non-commercial  ^ds; 
$10  per  25  words  for  business  ventures.  No  display 
ads  or  agency  discount.  Include  your  check  with 
order.  Deadline  for  ads  is  the  Ist  of  the  month  two 
months  prior  to  publication.  For  example:  January 
Ist  15  the  deadline  for  the  March  issue  which  will 
be  mailed  on  the  10th  of  February.  Type  copy. 
Fhrase  and  punctuate  exactly  as  you  wish  it  to 
appear.  No  all-capital  ads.  We  will  be  the  judge  of 
suitability  of  ads.  Our  responsibility  for  errors 
extends  only  to  printing  a  correct  ad  in  a  later 
issue.  We  cannot  check  into  each  advertiser,  so 
Caveat  Emptor  •  -  * 

FOR  SALE:  Old  73's  complete  sets:  '64,  '65,  '67; 
nearly  complete:  '61,  '63,  '66,  '68,  Make  offers* 
Paul  Capitolo,  W6RQG,  1735  LeRoy  Ave.,  Ber- 
Ikeley,  CA  94709 

3  PLASTIC  HOLDERS  will  frame  and  protect  60 
cards,  $1— or  10  holders  $3.  Prepaid  &  guaranteed. 
Patent  3309805.     Tepabco,  Box  198N,  Gallatin, 
ITennessee  37066* 


RTTY  GEAR  FOR  SALE*  List  issued  monthly,  88 
or  44  MHy  torroids  5  for  $1,50  postpaid.  Elliott 
Buchanan  8e  Associates,  Inc.,  1067  Mandana  Blvd., 
Oakland,  California  94610, 

"TOWER  HEADQUARTERSI"  11  Brands!  Heights 

aluminum  35%  off!  Strato  Crank-ups-low  costi 
Rotors,  antennas  and  gear  discounts.  Phone  patch 
$1 1 .95.  Catalog-20^  postage.  Brownville  Sales  Co. 
Stanley.  Wisconsin  54768. 

SELL:  COLLINS  KWS-1,  Ser.  896,  $640;  75A4, 
Ser.  5763.  S420-or  both  for  SI 025.  I  will  ship. 
Lew  Hindert,  Rt.  4,  Box  290,  New  Braunfels, 
Texas  78130. 

ON  AIR  NOW:  Complete  SSB  xmitter-Apache 
plus  SSB  adaptor  pfus  mike.  Mint  cond.  All  new 
tubes.  $150.  J:  F,  Weatherly  K1ZYQ,  473  Auburn, 
Newton,  MA. 

JOB  WANTED^  15  years  experience  writing  and 
teaching,  12  years  writing  in  space  program.  Have 

first  telegraph  and  phone  licenses.  Now  in  New 
England,  but  can  relocate.  Anyone  need  a  good 
experienced  writer?  Box  0-1,  c/o  73,  Peter* 
borough,  NH  03458. 

CHRISTIAN  Ham  Fellowship  now  organized  for 
Christian  hams  to  have  fellowship,  to  do  tract  work 
among  hams.  Christian  Hamm  Callbook  $1  donat- 
ion. Christian  Ham  Fellowship,  Box  218,  Holland, 
Michigan  49423, 

SWAP  MEASUREMENTS  Model  59  GDO,  excel- 
lent with  manual  for  Freq.  meter  TS-323  with  data 
20-480  mhz.  Gordon  W2IVIPT,  25  Norma  Ave,, 
Lincroft,  NJ  07738, 

SASEAQUARTER  coin  bring  GE  QSLs 
P247-"73/'  W2RUT,  Box  275,  Fair  Haven,  NY 
13064. 


SURPLUS  PARTS 

Latching  Relay  -  Potter  fit  Brumfreld  KB,  3PDT. 
1 1 5  V.  60  start,  6  v  60  stop.  The  2  relays  can  be 
separated,  making  a  DPDT  relay  with  115  v, 
coil,  &  a  SPOT  with  6  v.  coil.  5  amp  contacts. 
$1 ,25  each,  6  for  $6  00. 

POWER  TRANSFORMER,  275  v.  no  ct,  150 
ma.,  12  V.  @  2  amps  1 1 5  v.  60  pri,  2  3/4"  x  4" 
X  3y/^  h.  Shpg.  wvt.  7  lbs,  $1.75  each,  4  for 
S6.00, 

POWER  TRANS.,  3500-350  v  @  130  ma,  6.3 
V.  @  3.6  A,,  5  V.  @  3  A,  IT 5/230  v.  pri.  Open 
frame  with  leads,  Shpg  wt.  7  fbs.  $2.00. 
.5  mf  400  V,  oil-filled  capacitors,  rectangular 
case,  mil.  spec.  SI  .00  per  dozen. 
Loading  capacitor,  5-sections,  400  pf  per  sec- 
tion, 3/8"  shaft.  Will  load  full  power  into  50 
ohms.  $2.00  each.  Adapter  to  !4"  shaft.  25rf. 
Shpg.  wt.  4  lbs. 

1-inch    PM    speakers.      5,4  ohms.      A[so   make 
good  mike.   American  made.   75i  each. 
Transistors:      2^1187,    2N13n,   2N586.      15^ 
each,  25  for  $2.50. 

Command    XMTR    SPECIAL:       BC-457,   4-5.3 
Mc,  good  for  vfo  or  for  parts.    Fair  corrd.   Less 
tubes.     Shpg.   wt.   13  lbs.      S3. 00  each,  6  for 
S15  00 

GUARANTEED  USED  HAM  GEAR 

National  ISJC-303  with  calibrator.  Mint.  S200,00 


Mosley  CM-1  receiver 

Surplus  BC-348  wfth  AC  power. 

Galaxy  V  with  AC  supply. 

Heath  DX-IOOXmtr. 

Globe  Hybander  VHF  62  Xmtr. 

Hammarlund  HQ-140X  receiver. 


S  80.00 
S  70.00 
$300,00 
$  75-00 
$  49,00 
S10Q  00 


Hammarlund  HQ-145X  receiver  w/spkr  $160.00 

JEFF-TRDNICS 

4252  Pearl  Rd.  CIvlnd.O.  44109    749-4237 


BRIGAR 

ELECTRONICS 

10  ALICE  ST.  BINGHAMPTON,  INI.Y. 
13904,  AC  607  723-  3111 

*  COPPER  CLAD  PC  BOARDS.  6"  X  36" 

CC  both  sides  $2.16,  6"  X  9  3/4"  CC 
both  sides  60<!f,  7"  X  11  3/4"  C  one 
side  84(^,  5"  X  IVi"  CC  both  sides  40cf, 

*  STUD  MT  SILICON   RECTIFIERS  12 
amp,  50  PRV.  pkg  of  5  $1 .00 

*  ELECTROLYTICCAPACITOR1250mfd 

ISOvdc.  2"X4y4"  50dea. 

*  JUST  BOUGHT  OUT  ORIGINAL  CASE 

FOR  CB  RADIO.  Includes  mtg  bracket 
for  mobile  use  &  slide-in  chassis.  Holes 
pre-punched  for  power  transistor  &  pow- 
er cord.  May  be  used  for  mobile  power 
supplies,  P.A.  system  or  speaker  box  or 
many  other  uses.  Size  -  314"  H  X  7"  W 
X  872"  D.  Weight  3  lbs.  Original  cost 
$9.95.  Our  price  $1,95 

MIN  ORDER  $5.00 


il 


OCTOBER    1969 


141 


Send  254  for  Catalog  69-2 

VARIABLE    DISC 
TRIIVIMER 

Miniature  ceramic  variable 
trimmer  capacitor.  Piston  type 
tuning,  size  ,375  diam,  ,275 
deep.  Printed  circuit  mount. 
Amateur  net  on  this  is  SI. 68 
each.  Our  price  only  25i  each 
or  24  for  $5,00,  All  are  brand 
new.  State  size,  may  be  as- 
sorted if  you  wish. 

#N300       2,5-11  pf 

#NPO      5.5'18pf 

#N650       9-35  pf 


$€,400.00  MEMORY  DRUM 


Military  surplus  made  by*  HUGHES  for  the  AF, 
Condition  appears  excellent  due  to  being  enclosed 
in  air  tight  case  with  terminations  on  plug  con- 
nections. 134  read/write  heads,  12  heads  phase 
adjustable  timing.  Integral  drive  motor  115  volts 
400  cycle. 


Shipping  wt.  39  lbs. 


*  •  +  t  * 


.#DRUM  $100,00 


INTEGRATED  CIRCUrTS 


900 

Buffer 

$1  00 

910 

Dual  2-input  NOR 

1.00 

2-903 

Duaf  input  gate 

1.00 

914 

Dual  2'input  gate 

1.00 

914-925 

Dual  2-input  gate  dual 

expander 

1.00 

923 

JK  flip  flop 

1-00 

925 

Dual  2 -Input  gate  exp 

1.00 

946 

DTL  4  2  input  N  AND/NOR 

gate 

2/1.0O 

DTL  Clocked  flip  flop 

2/1.00 

tlVIB 

Dual  4-input  logic  gat© 

2/1.00 

7M6 

6  NPN  transistors  in  one 

package,  gen  use 

3/1.00 

12M2 

Diff  Amp 

1.00 

711 

Dual  Comp  Amp 

2.00 

JOHN   MESHNA  JR. 

19  ALLERTON  ST.,  LYNN,  MASS.  01904 
P.  O.  BOX  62,  E.  LYNN,  MASS.  01904 


MANUALS- TS323/UR,  TS-173/UR,  BC^38A, 
R-274/FRR,  TS-186D/UP,  SSB-100,  LM,  $5.00 
each.  Hundreds  of  others.  List  2Qi.  S.  Consalvo 
W3IHD,  4905  Roanne  Drive,  Washington,  DC 
2002 1 . 

TEXOMA  HAM  A  RAMA!  The  annual  Texoma 
Hamarama  will  by  held  again  Nov  15-16-17  at  the 
beautiful  Lake  Texoma  State  Lodge.  Plan  a  plea* 
sent  weekend  for  all.  Bring  the  family.  Mail 
registration  fee  of  $2  per  person  to:  Texoma 
Hamarama,  PO  Box  246,  Kingston,  OK  73439. 


GREENE   .  ,  center  dipote  insulator  with  . 
.  ,  without  balun  ,  .  see  September  73,  page  41, 


or 


QSLS????  Largest  variety  samples  25£  Sackers, 
WBDED,  Holland,  Michigan  49423, 

WANTED  MODEL  28KSR  in  good  operating 
condition  for  $250.00.  K.  Schwieker  K4KQR, 
1 124  Opelika  Road,  Auburn,  AL  36830. 

HEATHKIT  SB-110  and  Power  Supply  HP'23- 
Like  New-$270.00.  Charles  Kehter,  1067  Western 
Ave,,  Green  Bay,  Wl  54303. 

SSTV  MONITOR,  12  transistors,  5  tubes,  3RP7A 
CRT,  Bud  Portacab  cabinet,  tuning  indicator,  $190 
plus  shipping  costs,  Cohen  W4UMF,  6631  Wake- 
field Dr.,  Alexandria,  VA  22307. 

COLLINS  75 A4,  Serial  2530.  Excellent  condition. 
Best  offer  over  $300.00.  Paul  Delaney  WB6B0Q, 
1328  Calle  Pimiento,  Thousand  Oaks,  CA  91360. 

FOR  SALE:  HT-37-HT33A,  2000  watts,  PEP, 
Original  owner.  Good  condition.  $250.00.  Pickup 
only.  Fred  Fetherolf,  phone  614-332-3421,  Lauret- 
ville,OH  43135. 

ROCHESTER,  N.  Y.  is  again  Hamfest,  VHP  meet 
and  flea  market  headquarters  for  largest  event  in 
northeast.  May  16,  1970.  Write  WNY  Hamfest, 
Box  1388,  Rochester,  NY  14603. 

VHP  ROUNDUP  Syracuse  vhf  roundup  Oct.  11, 
1969,  Three  Rivers  Inn,  Rte  57,  10  miles  north 
Syracuse.  Tickets,  W2RHQ,  902  First  North  St., 
Syracuse,  NY  13208, 

TELETYPE  PICTURES  FOR  SALE.  50  pics  for 
$1.00.  Perforated  and  audio  tapes  available.  Write 
for  prices  specifying  speed  and  tracks.  Pictures  to 
be  included  in  second  volume  solicit^.  W9DGV, 
2210  30th  St.,  Rock  Island,  I L  61201. 

WARREN  COUNTY  N.  J.  W2JT/2,  October  18-19, 
3555,  7055,  14055,  21055,  28055,  3855,  7255, 
14255,  21355,  28555.  QSL  to  W2  bureau, 

HILLSBOROUGH  AMATEUR  RADIO  SOCIETY, 
INC,  iHARS)  Annual  Tampa,  Florida  Hamfest, 
Sunday,  October  12,  1969,  Lowry  Park.Sligh  Ave. 
&  North  Blvd,  Free  Parking— Many  Prizes. 

SELL:  ART-13  Transmitter  with  maintenance 
manual,  connectors,  spare  813,  837,  and  811's; 
$40,  RME  435 A  Receiver  with  book  and  some 
spare  tubes;  $60.  PCA-2  Panadaptor,  455  khz,  with 
book,  needs  work;  $5,  You  pay  shipping.  K9KRW, 
Sox  436,  Highland  Park,  IL  60035, 


142 


73  MAGAZINE 


MICRO*! 
AMP  METER 


/   - 


200 


*^^^V^^-  Texas 

Instrument" 

ISO  WATTS 

HIGH  FREQUENCY 


2N1907 


\  PNP 


urn 


Coll 
VGitagf 


Cirrrpnt 


150 


freq 

20120 

AMP  Imc. 


1400-PC.  GLASS  FIBER  OPTK  KIT 


It's  FUN* 


11  ^^ 


I  *• ' 


*\ 


it's  EducBtionatl  It's  Giftyf 

CI         ^  Make  light  *'pfpes 
C4  QQ    *  Daizimg  displays 
4>*f.O0    *  Triggers  photo  t 

infrared  cells 


»» 


.^ 


LIGHT 
GUIDE. 


orTlCAL  SCIENTIJ-JC  KREAKTH RU  f 
AUuwti  *'h»ir  ihin"  fflKan  fibcm  l2-rt.  kitnf  i 
til  IranKivift  4  rrci#vit  euld  lirHt  rnrmy  uT 
any  riilcur,  by  int^rnil  rvllf^tiMn.  Itundlrrl, 
jB^kptnl.  il  cutd«»^  «nuop«,  ptprs  Ur^^ 
jirriufiil  mrnrrnir  w»IU,  #v«i  in  ctTT:t«>i^  Iriv- 

ACTS  lik#  wtrv. 
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4ii  ti.-ililvl*V 


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Only  «nrV 
Itii    TflOO's    af   v«^ 


mwvr^kM4iwr   ilii,    *Sth    '^NjvIii' 


FAIRCHILD  '    BRf^J? 
"FLAT  PAK"         RTL 
INTEGRATED  CIRCUJTSs^* 

903-903*       3  Input  Gate  « «,..,,.,,,p.,,..$1 .69 

Half    Adder $1*69 

JK   Flip   Flop $1,69 

J  tV     Flip     Flop    *f*^tt*^m^m**»*m $1*96 

Quad   Inverter $1.69 

*First  time  anywhere  two  identical  IC'a  in  one 
packag'e,  example  923-923  contains  two  sepa* 
rate  JK  flip-flops   in  one  package. 

EPOXY   &  ^METAL  CASED  RECTIPrERS 


900 

903-903* 

904-904* 

923 
n    923-923* 
D    927 


1  AMP  1000  PIV  RECTrFlERS 

1  AMP   800   PIV    RECTIFIERS 

2  AMP  1000  PIV  RECTIFIERS 


5  for  $1 

6  for  $1 
4  for  $1 


709/1/^^ 


LOWEST   PRICES  ON 
LINEAR   AMPLIFIERS 

Guaranteed!  With  Spec.  Sheets' 


»*» 


11" 


\*  ' 


Type 
n  702 
3  709 
J  710 

a  711 


$2.22  s'o' 

Use 

DX.  Amplifier    

Operational  Amp 
OJfferentJaf  Comparator 
Sense  Amplifier 


lif11«1W'S1-fl 


MICRO  MINI 

"PORaElAIN** 

1    AMP 


O 


PIV 

SALt 

a    50 

.05 

n 

100 

.07 

n 

200 

,09 

I 

400 

.12 

r  ■ 

600 

.19 

1 

800 

.24 

n 

1000 

,29 

HAM 
StUCON 
TUBE 
SPECIALS 


(Replaces) 
niNT238     5U4G81    .. 

niN1239    5R41     , 

□  1N2637    866A)    .... 


piv 

50 
100 
200 
400 
600 
800 
1000 


1,5  AMP 


3  AMP 

n  .15 

1  .19 
H  .22 
H  -31 

H  -49 

n-79 


EPOXY  SILICON 
TRANSISTORS 


5  for  $1 


Type 
2N2222 
2N2368 
2N2711 
2N2368 
2N3396 
2N3565 
2N3568 
2N363d 
2N3641.3 
2N3645 
2N3662 
2N3683 
O    2N3793 
n    2N4248 
D    2N4284-5 
n    2N428a-9 
□    2N4290 


Sale 
5for  Jl 
5  for  $1 
5  for  $1 
5for$l 
5for$l 
5for$l 
5for$l 
5  for  » 1 
5  for$l 
5  for  $  1 
5  for  i  1 
5  for  $  1 
5  for  »1 
5for$l 
5for$l 
5for$l 
Sforfl 


HIGH  voir 

1  AMP 
EPDXY  /^ 


Piv 

n  2000' 
D  3000 

n  4000 

Q  5000 
n  6000 
□  8000 

n  10000 


SALE 

1.00 

1.35 

1.65 

2.25 

2.96 

3.50 

3,95 


'^  J.5  Amp  rating 


1  AMP 


PIV 
50 
100 
200 
400 
600 
800 
1000 


D  -32 


Terms:  adii  postaRe.  Rated:  net  30,  cod's  2!S% 
Phone  Orders:  W;^kefielii,  Mass.  (617)  2l5-382i> 
Rgtaii:  211  Aihian,  St..  W^ikefiyjd,  Mass. 

filANT  *JtMAS'  CATALOG  ON:  Parti,  RfCtifieri. 
.^  Transistfln,  SCRs,  UC.%  Equipment,   1  Oc 

P.O.  BOX  942  A 
Lynnfield.  Mass, 

01940 


POLY  PAKS 


400 


mc 


HIGH  POWER 
UHF    TRANSISTORS 

□    2N3632    23W.  3A. 


7  AMP  TRIACS 

PRV 
n     50 

n  100 

200 

[^  400 


OCTOBER    1969 


143 


mmm 


LIBERTY 
PAYS 


MORE! 


LIBERTY 
OFFERS 


MORE! 


WILL  BUY 
FOR  CASH 

ALL  TYPES 

ELECTRON  TUBES 
SEMICONDUCTORS 
Military  Electronic 

Equipment 
Test  Equipment 


WIRE,  WRITE,  PHONE  COLLECT!  WE  PAY 
FREIGHT  ON  All  PURCHASES  WE  MAKE 


PRESTEl  FIELD  STRENGTH  MEnR 

(Model   &T4G} 

^  Never  Anything  Like  It! 

%  7  !\/lan  Can  Do  a  Better  Job 

than  3  in  the  Same  Time! 

if  A  Gold-Mine  for  Antenna  Installers! 

Frequency  Range:  40  to  230 
and    470    to    860     Megaherin. 

Calibrated  outword  from  10 
to  50,000  Microvoitsp  Nothing 
makes  it  easier  to  properly  and 
speedily  find  the  correct  place 
to    install    TV,    FM    and    Com- 

^  munication  Antennas.  You  can 

measure   and    hear   the    signals 

volt    battery    economJcally    powered 

nothing   else   like  itl 


with    this   4V2 
unit*  There   is 


Only  $120.00   FOBN.  Y. 


Liberty  Electronics,  Inc. 

548  Broadway,  New  York,  New  York  10012,  Phone  212-925-6000 


40  METER  SUPER  GAIN  ANTENNA 

See  article  in  Oct.  '69,  73;  pg.  .  Potted,  precut  dipoie  7.2-7.3  iVIC.  2000  W  PEP,  50 
Ohms;  &  wire  for  reflector  screen.  All  u  need  is  five  8'  sticks.  Only  7' above  ground  but 
much  gain!!  SI 4.75  PPD  in  USA. 


SASE  for  tech.  data 


M 


OUSINR      ENTERPRISES 


571    Orange    Grove,    Melbourne,    F  la. 32901 


INDEX  TO  ADVERTISERS 


JeH-Tronics  141 


Aerotron  S7 

Epsilon  82 

AiTTateur  Wholesale  E  lee   43 

Essco  115 

Aineco  Books  1 1 

Evans  126 

American  Crvstal  93 

Anrenna  Mart  99 

Fair  Radio  101 

Arcturus  138 

Freck  79-101 

Arnold  103 
ATV  5B 

Galaxy    1-41 
Gateway  140 

B  «r  F  133 

Barker 'Williamson  75 
8»9elow  65*121 
Bob*s  AfTiaieur  67 

G  &  G  93 
Glass  131 
Global  101 
Good  hear  I  137 

Brigar  141 
Burghardl  97 

Hafstrom  23 
HAL  Devices  35 

Cal  book  57'97-140 

Hatrv  121 

HCJ  85 

CB  Radio  95 
Coax  Handbook   49 
Columbia  9B 

Heaih  5 
Henry  13 
H  &  L95 

DshI  93 

Instant  Gourmet  105 

Denson  121 
DGP  63 

International  Crystal  3 

Douv-Kev  27 
Dusina  144 

James  Research  53 
Jan  Crvstnl  75 

Lewispaul  137 
Lrberty  144 


Spectrum  103 
Stanley  82 
Swan  47 

Telrex  83 


MegarT  89 

Tower  140 

Meshna  142 

Two-Way  99 

Mlqrof  ect  131 

Military  Elec.  132 

UFO  Net  121 

United  Radio  139 

Natrona!  Radio  21 

Universal  81 

New  Ironies  IV 

Pantronics  93 

Vanguard  23-31  67-79-91 

Park   122 

Vibrople^  53 

Pickering  67 

PoiyPaks  143 

Western  95 

WR  L  35 

QKernent  33 

Word  OSL  101 

Radio  Shop  103 

Radio  Today  17 

73  IVlaga/rne                         ! 

Redline85-121 

Books  106  107 

Binders  81 

Sams  19 

Club  Fmagle99 

Schober  89 

Gunsmoke  139 

Security  91 

Radio  Bookshop  138 

Signal  One  III 

Subscnjjtions  1 15 

Slcip    103 

144 


73   MAGAZINE 


I 


COMPARE  IT? 


...WITH  WHAT? 


The  CX7  practicaUy  demands  comparison.  Question  is  *  ,  .  what  to  use  for  a  standard? 
A  transceiver?    Or  transmitter-receiver  separates? 

You'il  really  need  one  of  each.  Don't  forget  power  supplies,  speech  processor,  keyer, 
directional  wattmeter.  Pick  the  best.  In  fact^  set  up  your  "dream  station'"  ...  at  least 
on  paper.    NOW  ,  .  , 


WHATEVER  YOUR  CHOICE  IN  THE 

COMPARE  IT  PO I  NT-BY-POINT  with 

the  NO-COMPROMISE  CX7  .  .  . 

COMPARE  the  CX7  with  any  receiver  for 
sensitivity,  selectivity  options,  dynamic 
range,  AGC  merit,  VFO  smoothness,  inter- 
ference rejection  , . . 

COMPARE  the  CX7  with  any  transmitter 
for  continuous  power  output  in  all  modes, 
P. A.  ruggedness,  crisp  audio  punch,  low 
distortion,  instant  CW  break-in  and  spotting, 
quick  band-change  .  .  , 


COMPARE  the  CX7  with  any  transceiver 
for  total  size  and  weight ,  .  ,  the  extreme 
flexibility  of  its  dual-channel  system  .  .  .  the 
convenience  of  its  completely  selfxontained 
design  . . . 

CONSIDER  the  CX7's  incomparable  fre- 
quency coverage  and  readout  precision  ,  , , 
aerospace-bred  excellence  in  engineering 
and  craftsmanship  ...  built-in  "extras 
overall  versatility  .  . . 
SEE  WHAT  YOU'VE  BEEN  MISSING? 


'7f  Speaks  for  Itseir 


*t 


*       <        V 


Write  for  detaHed  mchnicai  information. 


A  Division  of  ECl  {An  NCR  Subsidiary  J 
2200  Anvil  Street  N.    •St.  Petersburg,  Florida  33710 


m 


( 


I 


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TRAP  VERTICAL 

ANTENNAS 


1 


See  your 
distributor  or 
write  for 
new  catalog 


I 


/ 


15800  Commerce  Park  Drive 

Brook  Park,  Ohio  44142 

Phone  (216)  267-3150 


i